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1.  Optimising case definitions of upper limb disorder for aetiological research and prevention – a review 
Experts disagree about the optimal classification of upper limb disorders (ULDs). To explore whether differences in associations with occupational risk factors offer a basis for choosing between case definitions in aetiological research and surveillance, we analysed previously published research.
Eligible reports (those with estimates of relative risk (RR) for >1 case definition relative to identical exposures were identified from systematic reviews of ULD and occupation and by hand-searching five peer-review journals published between January 1990 and June 2010. We abstracted details by anatomical site of the case and exposure definitions employed and paired estimates of RR, for alternative case definitions with identical occupational exposures. Pairs of case definitions were typically nested, a stricter definition being a subset of a simpler version. Differences in RR between paired definitions were expressed as the ratio of RRs, using that for the simpler definition as the denominator.
We found 21 reports, yielding 320 pairs of RRs (82, 75 and 163 respectively at the shoulder, elbow, and distal arm). Ratios of RRs were frequently ≤1 (46%), the median ratio overall and by anatomical site being close to unity. In only 2% of comparisons did ratios reach ≥4.
Complex ULD case definitions (e.g. involving physical signs, more specific symptom patterns, and investigations) yield similar associations with occupational risk factors to those using simpler definitions. Thus, in population-based aetiological research and surveillance, simple case definitions should normally suffice. Data on risk factors can justifiably be pooled in meta-analyses, despite differences in case definition.
PMCID: PMC3427012  PMID: 22006938
2.  In Vitro Fertilization and Multiple Pregnancies 
Executive Summary
The objective of this health technology policy assessment was to determine the clinical effectiveness and cost-effectiveness of IVF for infertility treatment, as well as the role of IVF in reducing the rate of multiple pregnancies.
Clinical Need: Target Population and Condition
Typically defined as a failure to conceive after a year of regular unprotected intercourse, infertility affects 8% to 16% of reproductive age couples. The condition can be caused by disruptions at various steps of the reproductive process. Major causes of infertility include abnormalities of sperm, tubal obstruction, endometriosis, ovulatory disorder, and idiopathic infertility. Depending on the cause and patient characteristics, management options range from pharmacologic treatment to more advanced techniques referred to as assisted reproductive technologies (ART). ART include IVF and IVF-related procedures such as intra-cytoplasmic sperm injection (ICSI) and, according to some definitions, intra-uterine insemination (IUI), also known as artificial insemination. Almost invariably, an initial step in ART is controlled ovarian stimulation (COS), which leads to a significantly higher rate of multiple pregnancies after ART compared with that following natural conception. Multiple pregnancies are associated with a broad range of negative consequences for both mother and fetuses. Maternal complications include increased risk of pregnancy-induced hypertension, pre-eclampsia, polyhydramnios, gestational diabetes, fetal malpresentation requiring Caesarean section, postpartum haemorrhage, and postpartum depression. Babies from multiple pregnancies are at a significantly higher risk of early death, prematurity, and low birth weight, as well as mental and physical disabilities related to prematurity. Increased maternal and fetal morbidity leads to higher perinatal and neonatal costs of multiple pregnancies, as well as subsequent lifelong costs due to disabilities and an increased need for medical and social support.
The Technology Being Reviewed
IVF was first developed as a method to overcome bilateral Fallopian tube obstruction. The procedure includes several steps: (1) the woman’s egg is retrieved from the ovaries; (2) exposed to sperm outside the body and fertilized; (3) the embryo(s) is cultured for 3 to 5 days; and (4) is transferred back to the uterus. IFV is considered to be one of the most effective treatments for infertility today. According to data from the Canadian Assisted Reproductive Technology Registry, the average live birth rate after IVF in Canada is around 30%, but there is considerable variation in the age of the mother and primary cause of infertility.
An important advantage of IVF is that it allows for the control of the number of embryos transferred. An elective single embryo transfer in IVF cycles adopted in many European countries was shown to significantly reduce the risk of multiple pregnancies while maintaining acceptable birth rates. However, when number of embryos transferred is not limited, the rate of IVF-associated multiple pregnancies is similar to that of other treatments involving ovarian stimulation. The practice of multiple embryo transfer in IVF is often the result of pressures to increase success rates due to the high costs of the procedure. The average rate of multiple pregnancies resulting from IVF in Canada is currently around 30%.
An alternative to IVF is IUI. In spite of reported lower success rates of IUI (pregnancy rates per cycle range from 8.7% to 17.1%) it is generally attempted before IVF due to its lower invasiveness and cost.
Two major drawbacks of IUI are that it cannot be used in cases of bilateral tubal obstruction and it does not allow much control over the risk of multiple pregnancies compared with IVF. The rate of multiple pregnancies after IUI with COS is estimated to be about 21% to 29%.
Ontario Health Insurance Plan Coverage
Currently, the Ontario Health Insurance Plan covers the cost of IVF for women with bilaterally blocked Fallopian tubes only, in which case it is funded for 3 cycles, excluding the cost of drugs. The cost of IUI is covered except for preparation of the sperm and drugs used for COS.
Diffusion of Technology
According to Canadian Assisted Reproductive Technology Registry data, in 2004 there were 25 infertility clinics across Canada offering IVF and 7,619 IVF cycles performed. In Ontario, there are 13 infertility clinics with about 4,300 IVF cycles performed annually.
Literature Review
Royal Commission Report on Reproductive Technologies
The 1993 release of the Royal Commission report on reproductive technologies, Proceed With Care, resulted in the withdrawal of most IVF funding in Ontario, where prior to 1994 IVF was fully funded. Recommendations of the Commission to withdraw IVF funding were largely based on findings of the systematic review of randomized controlled trials (RCTs) published before 1990. The review showed IVF effectiveness only in cases of bilateral tubal obstruction. As for nontubal causes of infertility, there was not enough evidence to establish whether IVF was effective or not.
Since the field of reproductive technology is constantly evolving, there have been several changes since the publication of the Royal Commission report. These changes include: increased success rates of IVF; introduction of ICSI in the early 1990’s as a treatment for male factor infertility; and improved embryo implantation rates allowing for the transfer of a single embryo to avoid multiple pregnancies after IVF.
Studies After the Royal Commission Report: Review Strategy
Three separate literature reviews were conducted in the following areas: clinical effectiveness of IVF, cost-effectiveness of IVF, and outcomes of single embryo transfer (SET) in IVF cycles.
Clinical effectiveness of IVF: RCTs or meta-analyses of RCTs that compared live birth rates after IVF versus alternative treatments, where the cause of infertility was clearly stated or it was possible to stratify the outcome by the cause of infertility.
Cost effectiveness of IVF: All relevant economic studies comparing IVF to alternative methods of treatment were reviewed
Outcomes of IVF with SET: RCTs or meta-analyses of RCTs that compared live birth rates and multiple birth rates associated with transfer of single versus double embryos.
OVID MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, EMBASE, Cochrane Library, the International Agency for Health Technology Assessment database, and websites of other health technology assessment agencies were searched using specific subject headings and keywords to identify relevant studies.
Summary of Findings
Comparative Clinical Effectiveness of IVF
Overall, there is a lack of well composed RCTs in this area and considerable diversity in both definition and measurement of outcomes exists between trials. Many studies used fertility or pregnancy rates instead of live birth rates. Moreover, the denominator for rate calculation varied from study to study (e.g. rates were calculated per cycle started, per cycle completed, per couple, etc...).
Nevertheless, few studies of sufficient quality were identified and categorized by the cause of infertility and existing alternatives to IVF. The following are the key findings:
A 2005 meta-analysis demonstrated that, in patients with idiopathic infertility, IVF was clearly superior to expectant management, but there were no statistically significant differences in live birth rates between IVF and IUI, nor between IVF and gamete-intra-Fallopian transfer.
A subset of data from a 2000 study showed no significant differences in pregnancy rates between IVF and IUI for moderate male factor infertility.
In patients with moderate male factor infertility, standard IVF was also compared with ICSI in a 2002 meta-analysis. All studies included in the meta-analysis showed superior fertilization rates with ICSI, and the pooled risk ratio for oocyte fertilization was 1.9 (95% Confidence Interval 1.4-2.5) in favour of ICSI. Two other RCTs in this area published after the 2002 meta-analysis had similar results and further confirmed these findings. There were no RCTs comparing IVF with ICSI in patients with severe male factor infertility, mainly because based on the expert opinion, ICSI might only be an effective treatment for severe male factor infertility.
Cost-Effectiveness of IVF
Five economic evaluations of IVF were found, including one comprehensive systematic review of 57 health economic studies. The studies compared cost-effectiveness of IVF with a number of alternatives such as observation, ovarian stimulation, IUI, tubal surgery, varicocelectomy, etc... The cost-effectiveness of IVF was analyzed separately for different types of infertility. Most of the reviewed studies concluded that due to the high cost, IVF has a less favourable cost-effectiveness profile compared with alternative treatment options. Therefore, IVF was not recommended as the first line of treatment in the majority of cases. The only two exceptions were bilateral tubal obstruction and severe male factor infertility, where an immediate offer of IVF/ICSI might the most cost-effective option.
Clinical Outcomes After Single Versus Double Embryo Transfer Strategies of IVF
Since the SET strategy has been more widely adopted in Europe, all RCT outcomes of SET were conducted in European countries. The major study in this area was a large 2005 meta-analysis, followed by two other published RCTs.
All of these studies reached similar conclusions:
Although a single SET cycle results in lower birth rates than a single double embryo transfer (DET) cycle, the cumulative birth rate after 2 cycles of SET (fresh + frozen-thawed embryos) was comparable to the birth rate after a single DET cycle (~40%).
SET was associated with a significant reduction in multiple births compared with DET (0.8% vs. 33.1% respectively in the largest RCT).
Most trials on SET included women younger than 36 years old with a sufficient number of embryos available for transfer that allowed for selection of the top quality embryo(s). A 2006 RCT, however, compared SET and DET strategies in an unselected group of patients without restrictions on the woman’s age or embryo quality. This study demonstrated that SET could be applied to older women.
Estimate of the Target Population
Based on results of the literature review and consultations with experts, four categories of infertile patients who may benefit from increased access to IVF/ICSI were identified:
Patients with severe male factor infertility, where IVF should be offered in conjunction with ICSI;
Infertile women with serious medical contraindications to multiple pregnancy, who should be offered IVF-SET;
Infertile patients who want to avoid the risk of multiple pregnancy and thus opt for IVF-SET; and
Patients who failed treatment with IUI and wish to try IVF.
Since, however, the latter indication does not reflect any new advances in IVF technology that would alter existing policy, it was not considered in this analysis.
Economic Analysis
Economic Review: Cost–Effectiveness of SET Versus DET
Conclusions of published studies on cost-effectiveness of SET versus DET were not consistent. While some studies found that SET strategy is more cost-effective due to avoidance of multiple pregnancies, other studies either did not find any significant differences in cost per birth between SET and DET, or favoured DET as a more cost-effective option.
Ontario-Based Economic Analysis
An Ontario-based economic analysis compared cost per birth using three treatment strategies: IUI, IVF-SET, and IVF-DET. A decision-tree model assumed three cycles for each treatment option. Two separate models were considered; the first included only fresh cycles of IVF, while the second had a combination of fresh and frozen cycles. Even after accounting for cost-savings due to avoidance of multiple pregnancies (only short-term complications), IVF-SET was still associated with a highest cost per birth. The approximate budget impact to cover the first three indications for IVF listed above (severe male factor infertility, women with medical contraindications to multiple pregnancy, and couples who wish to avoid the risk of multiple pregnancy) is estimated at $9.8 to $12.8 million (Cdn). Coverage of only first two indications, namely, ICSI in patients with severe male factor infertility and infertile women with serious medical contraindications to multiple pregnancy, is estimated at $3.8 to $5.5 million Cdn.
Other Considerations
International data shows that both IVF utilization and the average number of embryos transferred in IVF cycles are influenced by IVF funding policy. The success of the SET strategy in European countries is largely due to the fact that IVF treatment is subsidized by governments.
Surveys of patients with infertility demonstrated that a significant proportion (~40%) of patients not only do not mind having multiple babies, but consider twins being an ideal outcome of infertility treatment.
A women’s age may impose some restrictions on the implementation of a SET strategy.
Conclusions and Recommendations
A review of published studies has demonstrated that IVF-SET is an effective treatment for infertility that avoids multiple pregnancies.
However, results of an Ontario-based economic analysis shows that cost savings associated with a reduction in multiple pregnancies after IVF-SET does not justify the cost of universal IVF-SET coverage by the province. Moreover, the province currently funds IUI, which has been shown to be as effective as IVF for certain types of infertility and is significantly less expensive.
In patients with severe male factor infertility, IVF in conjunction with ICSI may be the only effective treatment.
Thus, 2 indications where additional IVF access should be considered include:
IVF/ICSI for patients with severe male factor infertility
IVF-SET in infertile women with serious medical contraindications to multiple pregnancy
PMCID: PMC3379537  PMID: 23074488
3.  Intervention randomized controlled trials involving wrist and shoulder arthroscopy: a systematic review 
Although arthroscopy of upper extremity joints was initially a diagnostic tool, it is increasingly used for therapeutic interventions. Randomized controlled trials (RCTs) are considered the gold standard for assessing treatment efficacy. We aimed to review the literature for intervention RCTs involving wrist and shoulder arthroscopy.
We performed a systematic review for RCTs in which at least one arm was an intervention performed through wrist arthroscopy or shoulder arthroscopy. PubMed and Cochrane Library databases were searched up to December 2012. Two researchers reviewed each article and recorded the condition treated, randomization method, number of randomized participants, time of randomization, outcomes measures, blinding, and description of dropouts and withdrawals. We used the modified Jadad scale that considers the randomization method, blinding, and dropouts/withdrawals; score 0 (lowest quality) to 5 (highest quality). The scores for the wrist and shoulder RCTs were compared with the Mann–Whitney test.
The first references to both wrist and shoulder arthroscopy appeared in the late 1970s. The search found 4 wrist arthroscopy intervention RCTs (Kienböck’s disease, dorsal wrist ganglia, volar wrist ganglia, and distal radius fracture; first 3 compared arthroscopic with open surgery). The median number of participants was 45. The search found 50 shoulder arthroscopy intervention RCTs (rotator cuff tears 22, instability 14, impingement 9, and other conditions 5). Of these, 31 compared different arthroscopic treatments, 12 compared arthroscopic with open treatment, and 7 compared arthroscopic with nonoperative treatment. The median number of participants was 60. The median modified Jadad score for the wrist RCTs was 0.5 (range 0–1) and for the shoulder RCTs 3.0 (range 0–5) (p = 0.012).
Despite the increasing use of wrist arthroscopy in the treatment of various wrist disorders the efficacy of arthroscopically performed wrist interventions has been studied in only 4 randomized studies compared to 50 randomized studies of significantly higher quality assessing interventions performed through shoulder arthroscopy.
PMCID: PMC4123827  PMID: 25059881
Arthroscopy; Wrist; Shoulder; Randomized trials; Jadad scale; Intervention RCT; Systematic review
4.  Stenting for Peripheral Artery Disease of the Lower Extremities 
Executive Summary
In January 2010, the Medical Advisory Secretariat received an application from University Health Network to provide an evidentiary platform on stenting as a treatment management for peripheral artery disease. The purpose of this health technology assessment is to examine the effectiveness of primary stenting as a treatment management for peripheral artery disease of the lower extremities.
Clinical Need: Condition and Target Population
Peripheral artery disease (PAD) is a progressive disease occurring as a result of plaque accumulation (atherosclerosis) in the arterial system that carries blood to the extremities (arms and legs) as well as vital organs. The vessels that are most affected by PAD are the arteries of the lower extremities, the aorta, the visceral arterial branches, the carotid arteries and the arteries of the upper limbs. In the lower extremities, PAD affects three major arterial segments i) aortic-iliac, ii) femoro-popliteal (FP) and iii) infra-popliteal (primarily tibial) arteries. The disease is commonly classified clinically as asymptomatic claudication, rest pain and critical ischemia.
Although the prevalence of PAD in Canada is not known, it is estimated that 800,000 Canadians have PAD. The 2007 Trans Atlantic Intersociety Consensus (TASC) II Working Group for the Management of Peripheral Disease estimated that the prevalence of PAD in Europe and North America to be 27 million, of whom 88,000 are hospitalizations involving lower extremities. A higher prevalence of PAD among elderly individuals has been reported to range from 12% to 29%. The National Health and Nutrition Examination Survey (NHANES) estimated that the prevalence of PAD is 14.5% among individuals 70 years of age and over.
Modifiable and non-modifiable risk factors associated with PAD include advanced age, male gender, family history, smoking, diabetes, hypertension and hyperlipidemia. PAD is a strong predictor of myocardial infarction (MI), stroke and cardiovascular death. Annually, approximately 10% of ischemic cardiovascular and cerebrovascular events can be attributed to the progression of PAD. Compared with patients without PAD, the 10-year risk of all-cause mortality is 3-fold higher in patients with PAD with 4-5 times greater risk of dying from cardiovascular event. The risk of coronary heart disease is 6 times greater and increases 15-fold in patients with advanced or severe PAD. Among subjects with diabetes, the risk of PAD is often severe and associated with extensive arterial calcification. In these patients the risk of PAD increases two to four fold. The results of the Canadian public survey of knowledge of PAD demonstrated that Canadians are unaware of the morbidity and mortality associated with PAD. Despite its prevalence and cardiovascular risk implications, only 25% of PAD patients are undergoing treatment.
The diagnosis of PAD is difficult as most patients remain asymptomatic for many years. Symptoms do not present until there is at least 50% narrowing of an artery. In the general population, only 10% of persons with PAD have classic symptoms of claudication, 40% do not complain of leg pain, while the remaining 50% have a variety of leg symptoms different from classic claudication. The severity of symptoms depends on the degree of stenosis. The need to intervene is more urgent in patients with limb threatening ischemia as manifested by night pain, rest pain, ischemic ulcers or gangrene. Without successful revascularization those with critical ischemia have a limb loss (amputation) rate of 80-90% in one year.
Diagnosis of PAD is generally non-invasive and can be performed in the physician offices or on an outpatient basis in a hospital. Most common diagnostic procedure include: 1) Ankle Brachial Index (ABI), a ratio of the blood pressure readings between the highest ankle pressure and the highest brachial (arm) pressure; and 2) Doppler ultrasonography, a diagnostic imaging procedure that uses a combination of ultrasound and wave form recordings to evaluate arterial flow in blood vessels. The value of the ABI can provide an assessment of the severity of the disease. Other non invasive imaging techniques include: Computed Tomography (CT) and Magnetic Resonance Angiography (MRA). Definitive diagnosis of PAD can be made by an invasive catheter based angiography procedure which shows the roadmap of the arteries, depicting the exact location and length of the stenosis / occlusion. Angiography is the standard method against which all other imaging procedures are compared for accuracy.
More than 70% of the patients diagnosed with PAD remain stable or improve with conservative management of pharmacologic agents and life style modifications. Significant PAD symptoms are well known to negatively influence an individual quality of life. For those who do not improve, revascularization methods either invasive or non-invasive can be used to restore peripheral circulation.
Technology Under Review
A Stent is a wire mesh “scaffold” that is permanently implanted in the artery to keep the artery open and can be combined with angioplasty to treat PAD. There are two types of stents: i) balloon-expandable and ii) self expandable stents and are available in varying length. The former uses an angioplasty balloon to expand and set the stent within the arterial segment. Recently, drug-eluting stents have been developed and these types of stents release small amounts of medication intended to reduce neointimal hyperplasia, which can cause re-stenosis at the stent site. Endovascular stenting avoids the problem of early elastic recoil, residual stenosis and flow limiting dissection after balloon angioplasty.
Research Questions
In individuals with PAD of the lower extremities (superficial femoral artery, infra-popliteal, crural and iliac artery stenosis or occlusion), is primary stenting more effective than percutaneous transluminal angioplasty (PTA) in improving patency?
In individuals with PAD of the lower extremities (superficial femoral artery, infra-popliteal, crural and iliac artery stenosis or occlusion), does primary stenting provide immediate success compared to PTA?
In individuals with PAD of the lower extremities (superficial femoral artery, infra-popliteal, crural and iliac artery stenosis or occlusion), is primary stenting associated with less complications compared to PTA?
In individuals with PAD of the lower extremities (superficial femoral artery, infra-popliteal, crural and iliac artery stenosis or occlusion), does primary stenting compared to PTA reduce the rate of re-intervention?
In individuals with PAD of the lower extremities (superficial femoral artery, infra-popliteal, crural and iliac artery stenosis or occlusion) is primary stenting more effective than PTA in improving clinical and hemodynamic success?
Are drug eluting stents more effective than bare stents in improving patency, reducing rates of re-interventions or complications?
Research Methods
Literature Search
A literature search was performed on February 2, 2010 using OVID MEDLINE, MEDLINE In-Process and Other Non-Indexed Citations, OVID EMBASE, the Cochrane Library, and the International Agency for Health Technology Assessment (INAHTA). Abstracts were reviewed by a single reviewer and, for those studies meeting the eligibility criteria, full-text articles were obtained. Reference lists were also examined for any additional relevant studies not identified through the search. The quality of evidence was assessed as high, moderate, low or very low according to GRADE methodology.
Inclusion Criteria
English language full-reports from 1950 to January Week 3, 2010
Comparative randomized controlled trials (RCTs), systematic reviews and meta-analyses of RCTs
Proven diagnosis of PAD of the lower extremities in all patients.
Adult patients at least 18 years of age.
Stent as at least one treatment arm.
Patency, re-stenosis, re-intervention, technical success, hemodynamic (ABI) and clinical improvement and complications as at least an outcome.
Exclusion Criteria
Non-randomized studies
Observational studies (cohort or retrospective studies) and case report
Feasibility studies
Studies that have evaluated stent but not as a primary intervention
Outcomes of Interest
The primary outcome measure was patency. Secondary measures included technical success, re-intervention, complications, hemodynamic (ankle brachial pressure index, treadmill walking distance) and clinical success or improvement according to Rutherford scale. It was anticipated, a priori, that there would be substantial differences among trials regarding the method of examination and definitions of patency or re-stenosis. Where studies reported only re-stenosis rates, patency rates were calculated as 1 minus re-stenosis rates.
Statistical Analysis
Odds ratios (for binary outcomes) or mean difference (for continuous outcomes) with 95% confidence intervals (CI) were calculated for each endpoint. An intention to treat principle (ITT) was used, with the total number of patients randomized to each study arm as the denominator for each proportion. Sensitivity analysis was performed using per protocol approach. A pooled odds ratio (POR) or mean difference for each endpoint was then calculated for all trials reporting that endpoint using a fixed effects model. PORs were calculated for comparisons of primary stenting versus PTA or other alternative procedures. Level of significance was set at alpha=0.05. Homogeneity was assessed using the chi-square test, I2 and by visual inspection of forest plots. If heterogeneity was encountered within groups (P < 0.10), a random effects model was used. All statistical analyses were performed using RevMan 5. Where sufficient data were available, these analyses were repeated within subgroups of patients defined by time of outcome assessment to evaluate sustainability of treatment benefit. Results were pooled based on the diseased artery and stent type.
Summary of Findings
Balloon-expandable stents vs PTA in superficial femoral artery disease
Based on a moderate quality of evidence, there is no significant difference in patency between primary stenting using balloon-expandable bare metal stents and PTA at 6, 12 and 24 months in patients with superficial femoral artery disease. The pooled OR for patency and their corresponding 95% CI are: 6 months 1.26 (0.74, 2.13); 12 months 0.95 (0.66, 1.38); and 24 months 0.72 (0.34. 1.55).
There is no significant difference in clinical improvement, re-interventions, peri and post operative complications, mortality and amputations between primary stenting using balloon-expandable bare stents and PTA in patients with superficial femoral artery. The pooled OR and their corresponding 95% CI are clinical improvement 0.85 (0.50, 1.42); ankle brachial index 0.01 (-0.02, 0.04) re-intervention 0.83 (0.26, 2.65); complications 0.73 (0.43, 1.22); all cause mortality 1.08 (0.59, 1.97) and amputation rates 0.41 (0.14, 1.18).
Self-expandable stents vs PTA in superficial femoral artery disease
Based on a moderate quality of evidence, primary stenting using self-expandable bare metal stents is associated with significant improvement in patency at 6, 12 and 24 months in patients with superficial femoral artery disease. The pooled OR for patency and their corresponding 95% CI are: 6 months 2.35 (1.06, 5.23); 12 months 1.54 (1.01, 2.35); and 24 months 2.18 (1.00. 4.78). However, the benefit of primary stenting is not observed for clinical improvement, re-interventions, peri and post operative complications, mortality and amputation in patients with superficial femoral artery disease. The pooled OR and their corresponding 95% CI are clinical improvement 0.61 (0.37, 1.01); ankle brachial index 0.01 (-0.06, 0.08) re-intervention 0.60 (0.36, 1.02); complications 1.60 (0.53, 4.85); all cause mortality 3.84 (0.74, 19.22) and amputation rates 1.96 (0.20, 18.86).
Balloon expandable stents vs PTA in iliac artery occlusive disease
Based on moderate quality of evidence, despite immediate technical success, 12.23 (7.17, 20.88), primary stenting is not associated with significant improvement in patency, clinical status, treadmill walking distance and reduction in re-intervention, complications, cardiovascular events, all cause mortality, QoL and amputation rates in patients with intermittent claudication caused by iliac artery occlusive disease. The pooled OR and their corresponding 95% CI are: patency 1.03 (0.56, 1.87); clinical improvement 1.08 (0.60, 1.94); walking distance 3.00 (12.96, 18.96); re-intervention 1.16 (0.71, 1.90); complications 0.56 (0.20, 1.53); all cause mortality 0.89 (0.47, 1.71); QoL 0.40 (-4.42, 5.52); cardiovascular event 1.16 (0.56, 2.40) and amputation rates 0.37 (0.11, 1.23). To date no RCTs are available evaluating self-expandable stents in the common or external iliac artery stenosis or occlusion.
Drug-eluting stent vs balloon-expandable bare metal stents in crural arteries
Based on a very low quality of evidence, at 6 months of follow-up, sirolimus drug-eluting stents are associated with a reduction in target vessel revascularization and re-stenosis rates in patients with atherosclerotic lesions of crural (tibial) arteries compared with balloon-expandable bare metal stent. The OR and their corresponding 95% CI are: re-stenosis 0.09 (0.03, 0.28) and TVR 0.15 (0.05, 0.47) in patients with atherosclerotic lesions of the crural arteries at 6 months follow-up. Both types of stents offer similar immediate success. Limitations of this study include: short follow-up period, small sample and no assessment of mortality as an outcome. Further research is needed to confirm its effect and safety.
PMCID: PMC3377569  PMID: 23074395
5.  Minimally invasive surgical procedures for the treatment of lumbar disc herniation 
In up to 30% of patients undergoing lumbar disc surgery for herniated or protruded discs outcomes are judged unfavourable. Over the last decades this problem has stimulated the development of a number of minimally-invasive operative procedures. The aim is to relieve pressure from compromised nerve roots by mechanically removing, dissolving or evaporating disc material while leaving bony structures and surrounding tissues as intact as possible. In Germany, there is hardly any utilisation data for these new procedures – data files from the statutory health insurances demonstrate that about 5% of all lumbar disc surgeries are performed using minimally-invasive techniques. Their real proportion is thought to be much higher because many procedures are offered by private hospitals and surgeries and are paid by private health insurers or patients themselves. So far no comprehensive assessment comparing efficacy, safety, effectiveness and cost-effectiveness of minimally-invasive lumbar disc surgery to standard procedures (microdiscectomy, open discectomy) which could serve as a basis for coverage decisions, has been published in Germany.
Against this background the aim of the following assessment is:
Based on published scientific literature assess safety, efficacy and effectiveness of minimally-invasive lumbar disc surgery compared to standard procedures. To identify and critically appraise studies comparing costs and cost-effectiveness of minimally-invasive procedures to that of standard procedures. If necessary identify research and evaluation needs and point out regulative needs within the German health care system. The assessment focusses on procedures that are used in elective lumbar disc surgery as alternative treatment options to microdiscectomy or open discectomy. Chemonucleolysis, percutaneous manual discectomy, automated percutaneous lumbar discectomy, laserdiscectomy and endoscopic procedures accessing the disc by a posterolateral or posterior approach are included.
In order to assess safety, efficacy and effectiveness of minimally-invasive procedures as well as their economic implications systematic reviews of the literature are performed. A comprehensive search strategy is composed to search 23 electronic databases, among them MEDLINE, EMBASE and the Cochrane Library. Methodological quality of systematic reviews, HTA reports and primary research is assessed using checklists of the German Scientific Working Group for Health Technology Assessment. Quality and transparency of cost analyses are documented using the quality and transparency catalogues of the working group. Study results are summarised in a qualitative manner. Due to the limited number and the low methodological quality of the studies it is not possible to conduct metaanalyses. In addition to the results of controlled trials results of recent case series are introduced and discussed.
The evidence-base to assess safety, efficacy and effectiveness of minimally-invasive lumbar disc surgery procedures is rather limited:
Percutaneous manual discectomy: Six case series (four after 1998)Automated percutaneous lumbar discectomy: Two RCT (one discontinued), twelve case series (one after 1998)Chemonucleolysis: Five RCT, five non-randomised controlled trials, eleven case seriesPercutaneous laserdiscectomy: One non-randomised controlled trial, 13 case series (eight after 1998)Endoscopic procedures: Three RCT, 21 case series (17 after 1998)
There are two economic analyses each retrieved for chemonucleolysis and automated percutaneous discectomy as well as one cost-minimisation analysis comparing costs of an endoscopic procedure to costs for open discectomy.
Among all minimally-invasive procedures chemonucleolysis is the only of which efficacy may be judged on the basis of results from high quality randomised controlled trials (RCT). Study results suggest that the procedure maybe (cost)effectively used as an intermediate therapeutical option between conservative and operative management of small lumbar disc herniations or protrusions causing sciatica. Two RCT comparing transforaminal endoscopic procedures with microdiscectomy in patients with sciatica and small non-sequestered disc herniations show comparable short and medium term overall success rates. Concerning speed of recovery and return to work a trend towards more favourable results for the endoscopic procedures is noted. It is doubtful though, whether these results from the eleven and five years old studies are still valid for the more advanced procedures used today. The only RCT comparing the results of automated percutaneous lumbar discectomy to those of microdiscectomy showed clearly superior results of microdiscectomy. Furthermore, success rates of automated percutaneous lumbar discectomy reported in the RCT (29%) differ extremely from success rates reported in case series (between 56% and 92%).
The literature search retrieves no controlled trials to assess efficacy and/or effectiveness of laser-discectomy, percutaneous manual discectomy or endoscopic procedures using a posterior approach in comparison to the standard procedures. Results from recent case series permit no assessment of efficacy, especially not in comparison to standard procedures. Due to highly selected patients, modi-fications of operative procedures, highly specialised surgical units and poorly standardised outcome assessment results of case series are highly variable, their generalisability is low.
The results of the five economical analyses are, due to conceptual and methodological problems, of no value for decision-making in the context of the German health care system.
Aside from low methodological study quality three conceptual problems complicate the interpretation of results.
Continuous further development of technologies leads to a diversity of procedures in use which prohibits generalisation of study results. However, diversity is noted not only for minimally-invasive procedures but also for the standard techniques against which the new developments are to be compared. The second problem refers to the heterogeneity of study populations. For most studies one common inclusion criterion was "persisting sciatica after a course of conservative treatment of variable duration". Differences among study populations are noted concerning results of imaging studies. Even within every group of minimally-invasive procedure, studies define their own in- and exclusion criteria which differ concerning degree of dislocation and sequestration of disc material. There is the non-standardised assessment of outcomes which are performed postoperatively after variable periods of time. Most studies report results in a dichotomous way as success or failure while the classification of a result is performed using a variety of different assessment instruments or procedures. Very often the global subjective judgement of results by patients or surgeons is reported. There are no scientific discussions whether these judgements are generalisable or comparable, especially among studies that are conducted under differing socio-cultural conditions. Taking into account the weak evidence-base for efficacy and effectiveness of minimally-invasive procedures it is not surprising that so far there are no dependable economic analyses.
Conclusions that can be drawn from the results of the present assessment refer in detail to the specified minimally-invasive procedures of lumbar disc surgery but they may also be considered exemplary for other fields where optimisation of results is attempted by technological development and widening of indications (e.g. total hip replacement).
Compared to standard technologies (open discectomy, microdiscectomy) and with the exception of chemonucleolysis, the developmental status of all other minimally-invasive procedures assessed must be termed experimental. To date there is no dependable evidence-base to recommend their use in routine clinical practice. To create such a dependable evidence-base further research in two directions is needed: a) The studies need to include adequate patient populations, use realistic controls (e.g. standard operative procedures or continued conservative care) and use standardised measurements of meaningful outcomes after adequate periods of time. b) Studies that are able to report effectiveness of the procedures under everyday practice conditions and furthermore have the potential to detect rare adverse effects are needed. In Sweden this type of data is yielded by national quality registries. On the one hand their data are used for quality improvement measures and on the other hand they allow comprehensive scientific evaluations. Since the year of 2000 a continuous rise in utilisation of minimally-invasive lumbar disc surgery is observed among statutory health insurers. Examples from other areas of innovative surgical technologies (e.g. robot assisted total hip replacement) indicate that the rise will probably continue - especially because there are no legal barriers to hinder introduction of innovative treatments into routine hospital care. Upon request by payers or providers the "Gemeinsamer Bundesausschuss" may assess a treatments benefit, its necessity and cost-effectiveness as a prerequisite for coverage by the statutory health insurance. In the case of minimally-invasive disc surgery it would be advisable to examine the legal framework for covering procedures only if they are provided under evaluation conditions. While in Germany coverage under evaluation conditions is established practice in ambulatory health care only (“Modellvorhaben") examples from other European countries (Great Britain, Switzerland) demonstrate that it is also feasible for hospital based interventions. In order to assure patient protection and at the same time not hinder the further development of new and promising technologies provision under evaluation conditions could also be realised in the private health care market - although in this sector coverage is not by law linked to benefit, necessity and cost-effectiveness of an intervention.
PMCID: PMC3011322  PMID: 21289928
6.  Greater Response to Placebo in Children Than in Adults: A Systematic Review and Meta-Analysis in Drug-Resistant Partial Epilepsy 
PLoS Medicine  2008;5(8):e166.
Despite guidelines establishing the need to perform comprehensive paediatric drug development programs, pivotal trials in children with epilepsy have been completed mostly in Phase IV as a postapproval replication of adult data. However, it has been shown that the treatment response in children can differ from that in adults. It has not been investigated whether differences in drug effect between adults and children might occur in the treatment of drug-resistant partial epilepsy, although such differences may have a substantial impact on the design and results of paediatric randomised controlled trials (RCTs).
Methods and Findings
Three electronic databases were searched for RCTs investigating any antiepileptic drug (AED) in the add-on treatment of drug-resistant partial epilepsy in both children and adults. The treatment effect was compared between the two age groups using the ratio of the relative risk (RR) of the 50% responder rate between active AEDs treatment and placebo groups, as well as meta-regression. Differences in the response to placebo and to active treatment were searched using logistic regression. A comparable approach was used for analysing secondary endpoints, including seizure-free rate, total and adverse events-related withdrawal rates, and withdrawal rate for seizure aggravation. Five AEDs were evaluated in both adults and children with drug-resistant partial epilepsy in 32 RCTs. The treatment effect was significantly lower in children than in adults (RR ratio: 0.67 [95% confidence interval (CI) 0.51–0.89]; p = 0.02 by meta-regression). This difference was related to an age-dependent variation in the response to placebo, with a higher rate in children than in adults (19% versus 9.9%, p < 0.001), whereas no significant difference was observed in the response to active treatment (37.2% versus 30.4%, p = 0.364). The relative risk of the total withdrawal rate was also significantly lower in children than in adults (RR ratio: 0.65 [95% CI 0.43–0.98], p = 0.004 by metaregression), due to higher withdrawal rate for seizure aggravation in children (5.6%) than in adults (0.7%) receiving placebo (p < 0.001). Finally, there was no significant difference in the seizure-free rate between adult and paediatric studies.
Children with drug-resistant partial epilepsy receiving placebo in double-blind RCTs demonstrated significantly greater 50% responder rate than adults, probably reflecting increased placebo and regression to the mean effects. Paediatric clinical trial designs should account for these age-dependent variations of the response to placebo to reduce the risk of an underestimated sample size that could result in falsely negative trials.
In a systematic review of antiepileptic drugs, Philippe Ryvlin and colleagues find that children with drug-resistant partial epilepsy enrolled in trials seem to have a greater response to placebo than adults enrolled in such trials.
Editors' Summary
Whenever an adult is given a drug to treat a specific condition, that drug will have been tested in “randomized controlled trials” (RCTs). In RCTs, a drug's effects are compared to those of another drug for the same condition (or to a placebo, dummy drug) by giving groups of adult patients the different treatments and measuring how well each drug deals with the condition and whether it has any other effects on the patients' health. However, many drugs given to children have only been tested in adults, the assumption being that children can safely take the same drugs as adults provided the dose is scaled down. This approach to treatment is generally taken in epilepsy, a common brain disorder in children in which disruptions in the electrical activity of part (partial epilepsy) or all (generalized epilepsy) of the brain cause seizures. The symptoms of epilepsy depend on which part of the brain is disrupted and can include abnormal sensations, loss of consciousness, or convulsions. Most but not all patients can be successfully treated with antiepileptic drugs, which reduce or stop the occurrence of seizures.
Why Was This Study Done?
It is increasingly clear that children and adults respond differently to many drugs, including antiepileptic drugs. For example, children often break down drugs differently from adults, so a safe dose for an adult may be fatal to a child even after scaling down for body size, or it may be ineffective because of quicker clearance from the child's body. Consequently, regulatory bodies around the world now require comprehensive drug development programs in children as well as in adults. However, for pediatric trials to yield useful results, the general differences in the treatment response between children and adults must first be determined and then allowed for in the design of pediatric RCTs. In this study, the researchers investigate whether there is any evidence in published RCTs for age-dependent differences in the response to antiepileptic drugs in drug-resistant partial epilepsy.
What Did the Researchers Do and Find?
The researchers searched the literature for reports of RCTs on the effects of antiepileptic drugs in the add-on treatment of drug-resistant partial epilepsy in children and in adults—that is, trials that compared the effects of giving an additional antiepileptic drug with those of giving a placebo by asking what fraction of patients given each treatment had a 50% reduction in seizure frequency during the treatment period compared to a baseline period (the “50% responder rate”). This “systematic review” yielded 32 RCTs, including five pediatric RCTs. The researchers then compared the treatment effect (the ratio of the 50% responder rate in the treatment arm to the placebo arm) in the two age groups using a statistical approach called “meta-analysis” to pool the results of these studies. The treatment effect, they report, was significantly lower in children than in adults. Further analysis indicated that this difference was because more children than adults responded to the placebo. Nearly 1 in 5 children had a 50% reduction in seizure rate when given a placebo compared to only 1 in 10 adults. About a third of both children and adults had a 50% reduction in seizure rate when given antiepileptic drugs.
What Do These Findings Mean?
These findings, although limited by the small number of pediatric trials done so far, suggest that children with drug-resistant partial epilepsy respond more strongly in RCTs to placebo than adults. Although additional studies need to be done to find an explanation for this observation and to discover whether anything similar occurs in other conditions, this difference between children and adults should be taken into account in the design of future pediatric trials on the effects of antiepileptic drugs, and possibly drugs for other conditions. Specifically, to reduce the risk of false-negative results, this finding suggests that it might be necessary to increase the size of future pediatric trials to ensure that the trials have enough power to discover effects of the drugs tested, if they exist.
Additional Information.
Please access these Web sites via the online version of this summary at
This study is further discussed in a PLoS Medicine Perspective by Terry Klassen and colleagues
The European Medicines Agency provides information about the regulation of medicines for children in Europe
The US Food and Drug Administration Office of Pediatric Therapeutics provides similar information for the US
The UK Medicines and Healthcare products Regulatory Agency also provides information on why medicines need to be tested in children
The MedlinePlus encyclopedia has a page on epilepsy (in English and Spanish)
The US National Institute for Neurological Disorders and Stroke and the UK National Health Service Direct health encyclopedia both provide information on epilepsy for patients (in several languages)
Neuroscience for Kids is an educational Web site prepared by Eric Chudler (University of Washington, Seattle, US) that includes information on epilepsy and a list of links to epilepsy organizations (mainly in English but some sections in other languages as well)
PMCID: PMC2504483  PMID: 18700812
7.  Strategies for Increasing Recruitment to Randomised Controlled Trials: Systematic Review 
PLoS Medicine  2010;7(11):e1000368.
Patrina Caldwell and colleagues performed a systematic review of randomized studies that compared methods of recruiting individual study participants into trials, and found that strategies that focus on increasing potential participants' awareness of the specific health problem, and that engaged them, appeared to increase recruitment.
Recruitment of participants into randomised controlled trials (RCTs) is critical for successful trial conduct. Although there have been two previous systematic reviews on related topics, the results (which identified specific interventions) were inconclusive and not generalizable. The aim of our study was to evaluate the relative effectiveness of recruitment strategies for participation in RCTs.
Methods and Findings
A systematic review, using the PRISMA guideline for reporting of systematic reviews, that compared methods of recruiting individual study participants into an actual or mock RCT were included. We searched MEDLINE, Embase, The Cochrane Library, and reference lists of relevant studies. From over 16,000 titles or abstracts reviewed, 396 papers were retrieved and 37 studies were included, in which 18,812 of at least 59,354 people approached agreed to participate in a clinical RCT. Recruitment strategies were broadly divided into four groups: novel trial designs (eight studies), recruiter differences (eight studies), incentives (two studies), and provision of trial information (19 studies). Strategies that increased people's awareness of the health problem being studied (e.g., an interactive computer program [relative risk (RR) 1.48, 95% confidence interval (CI) 1.00–2.18], attendance at an education session [RR 1.14, 95% CI 1.01–1.28], addition of a health questionnaire [RR 1.37, 95% CI 1.14–1.66]), or a video about the health condition (RR 1.75, 95% CI 1.11–2.74), and also monetary incentives (RR1.39, 95% CI 1.13–1.64 to RR 1.53, 95% CI 1.28–1.84) improved recruitment. Increasing patients' understanding of the trial process, recruiter differences, and various methods of randomisation and consent design did not show a difference in recruitment. Consent rates were also higher for nonblinded trial design, but differential loss to follow up between groups may jeopardise the study findings. The study's main limitation was the necessity of modifying the search strategy with subsequent search updates because of changes in MEDLINE definitions. The abstracts of previous versions of this systematic review were published in 2002 and 2007.
Recruitment strategies that focus on increasing potential participants' awareness of the health problem being studied, its potential impact on their health, and their engagement in the learning process appeared to increase recruitment to clinical studies. Further trials of recruitment strategies that target engaging participants to increase their awareness of the health problems being studied and the potential impact on their health may confirm this hypothesis.
Please see later in the article for the Editors' Summary
Editors' Summary
Before any health care intervention—a treatment for a disease or a measure such as vaccination that is designed to prevent an illness—is adopted by the medical community, it undergoes exhaustive laboratory-based and clinical research. In the laboratory, scientists investigate the causes of diseases, identify potential new treatments or preventive methods, and test these interventions in animals. New interventions that look hopeful are then investigated in clinical trials—studies that test these interventions in people by following a strict trial protocol or action plan. Phase I trials test interventions in a few healthy volunteers or patients to evaluate their safety and to identify possible side effects. In phase II trials, a larger group of patients receives an intervention to evaluate its safety further and to get an initial idea of its effectiveness. In phase III trials, very large groups of patients (sometimes in excess of a thousand people) are randomly assigned to receive the new intervention or an established intervention or placebo (dummy intervention). These “randomized controlled trials” or “RCTs” provide the most reliable information about the effectiveness and safety of health care interventions.
Why Was This Study Done?
Patients who participate in clinical trials must fulfill the inclusion criteria laid down in the trial protocol and must be given information about the trial, its risks, and potential benefits before agreeing to participate (informed consent). Unfortunately, many RCTs struggle to enroll the number of patients specified in their trial protocol, which can reduce a trial's ability to measure the effect of a new intervention. Inadequate recruitment can also increase costs and, in the worst cases, prevent trial completion. Several strategies have been developed to improve recruitment but it is not clear which strategy works best. In this study, the researchers undertake a systematic review (a study that uses predefined criteria to identify all the research on a given topic) of “recruitment trials”—studies that have randomly divided potential RCT participants into groups, applied different strategies for recruitment to each group, and compared recruitment rates in the groups.
What Did the Researchers Do and Find?
The researchers identified 37 randomized trials of recruitment strategies into real and mock RCTs (where no actual trial occurred). In all, 18,812 people agreed to participate in an RCT in these recruitment trials out of at least 59,354 people approached. Some of these trials investigated novel strategies for recruitment, such as changes in how patients are randomized. Others looked at the effect of recruiter differences (for example, increased contact between the health care professionals doing the recruiting and the trial investigators), the effect of offering monetary incentives to participants, and the effect of giving more information about the trial to potential participants. Recruitment strategies that improved people's awareness of the health problem being studied—provision of an interactive computer program or a video about the health condition, attendance at an educational session, or inclusion of a health questionnaire in the recruitment process—improved recruitment rates, as did monetary incentives. Increasing patients' understanding about the trial process itself, recruiter differences, and alterations in consent design and randomization generally had no effect on recruitment rates although consent rates were higher when patients knew the treatment to which they had been randomly allocated before consenting. However, differential losses among the patients in different treatment groups in such nonblinded trials may jeopardize study findings.
What Do These Findings Mean?
These findings suggest that trial recruitment strategies that focus on increasing the awareness of potential participants of the health problem being studied and its possible effects on their health, and that engage potential participants in the trial process are likely to increase recruitment to RCTs. The accuracy of these findings depends on whether the researchers identified all the published research on recruitment strategies and on whether other research on recruitment strategies has been undertaken and not published that could alter these findings. Furthermore, because about half of the recruitment trials identified by the researchers were undertaken in the US, the successful strategies identified here might not be generalizable to other countries. Nevertheless, these recruitment strategies should now be investigated further to ensure that the future evaluation of new health care interventions is not hampered by poor recruitment into RCTs.
Additional Information
Please access these Web sites via the online version of this summary at
The Web site is a searchable register of federally and privately supported clinical trials in the US and around the world, providing information about all aspects of clinical trials
The US National Institutes of Health provides information about clinical trials
The UK National Health Service Choices Web site has information for patients about clinical trials and medical research
The UK Medical Research Council Clinical Trials Units also provides information for patients about clinical trials and links to information on clinical trials provided by other organizations
MedlinePlus has links to further resources on clinical trials (in English and Spanish)
The Australian Government's National Health and Medical Research Council has information about clinical trials
WHO International Clinical Trials Registry Platform aims to ensure that all trials are publicly accessible to those making health care decisions
The Star Child Health International Forum of Standards for Research is a resource center for pediatric clinical trial design, conduct, and reporting
PMCID: PMC2976724  PMID: 21085696
8.  Differences in Reporting of Analyses in Internal Company Documents Versus Published Trial Reports: Comparisons in Industry-Sponsored Trials in Off-Label Uses of Gabapentin 
PLoS Medicine  2013;10(1):e1001378.
Using documents obtained through litigation, S. Swaroop Vedula and colleagues compared internal company documents regarding industry-sponsored trials of off-label uses of gabapentin with the published trial reports and find discrepancies in reporting of analyses.
Details about the type of analysis (e.g., intent to treat [ITT]) and definitions (i.e., criteria for including participants in the analysis) are necessary for interpreting a clinical trial's findings. Our objective was to compare the description of types of analyses and criteria for including participants in the publication (i.e., what was reported) with descriptions in the corresponding internal company documents (i.e., what was planned and what was done). Trials were for off-label uses of gabapentin sponsored by Pfizer and Parke-Davis, and documents were obtained through litigation.
Methods and Findings
For each trial, we compared internal company documents (protocols, statistical analysis plans, and research reports, all unpublished), with publications. One author extracted data and another verified, with a third person verifying discordant items and a sample of the rest. Extracted data included the number of participants randomized and analyzed for efficacy, and types of analyses for efficacy and safety and their definitions (i.e., criteria for including participants in each type of analysis). We identified 21 trials, 11 of which were published randomized controlled trials, and that provided the documents needed for planned comparisons. For three trials, there was disagreement on the number of randomized participants between the research report and publication. Seven types of efficacy analyses were described in the protocols, statistical analysis plans, and publications, including ITT and six others. The protocol or publication described ITT using six different definitions, resulting in frequent disagreements between the two documents (i.e., different numbers of participants were included in the analyses).
Descriptions of analyses conducted did not agree between internal company documents and what was publicly reported. Internal company documents provide extensive documentation of methods planned and used, and trial findings, and should be publicly accessible. Reporting standards for randomized controlled trials should recommend transparent descriptions and definitions of analyses performed and which study participants are excluded.
Please see later in the article for the Editors' Summary
Editors' Summary
To be credible, published research must present an unbiased, transparent, and accurate description of the study methods and findings so that readers can assess all relevant information to make informed decisions about the impact of any conclusions. Therefore, research publications should conform to universally adopted guidelines and checklists. Studies to establish whether a treatment is effective, termed randomized controlled trials (RCTs), are checked against a comprehensive set of guidelines: The robustness of trial protocols are measured through the Standard Protocol Items for Randomized Trials (SPIRIT), and the Consolidated Standards of Reporting Trials (CONSORT) statement (which was constructed and agreed by a meeting of journal editors in 1996, and has been updated over the years) includes a 25-point checklist that covers all of the key points in reporting RCTs.
Why Was This Study Done?
Although the CONSORT statement has helped improve transparency in the reporting of the methods and findings from RCTs, the statement does not define how certain types of analyses should be conducted and which patients should be included in the analyses, for example, in an intention-to-treat analysis (in which all participants are included in the data analysis of the group to which they were assigned, whether or not they completed the intervention given to the group). So in this study, the researchers used internal company documents released in the course of litigation against the pharmaceutical company Pfizer regarding the drug gabapentin, to compare between the internal and published reports the reporting of the numbers of participants, the description of the types of analyses, and the definitions of each type of analysis. The reports involved studies of gabapentin used for medical reasons not approved for marketing by the US Food and Drug Administration, known as “off-label” uses.
What Did the Researchers Do and Find?
The researchers identified trials sponsored by Pfizer relating to four off-label uses of gabapentin and examined the internal company protocols, statistical analysis plans, research reports, and the main publications related to each trial. The researchers then compared the numbers of participants randomized and analyzed for the main (primary) outcome and the type of analysis for efficacy and safety in both the internal research report and the trial publication. The researchers identified 21 trials, 11 of which were published RCTs that had the associated documents necessary for comparison.
The researchers found that in three out of ten trials there were differences in the internal research report and the main publication regarding the number of randomized participants. Furthermore, in six out of ten trials, the researchers were unable to compare the internal research report with the main publication for the number of participants analyzed for efficacy, because the research report either did not describe the primary outcome or did not describe the type of analysis. Overall, the researchers found that seven different types of efficacy analyses were described in the protocols, statistical analysis plans, and publications, including intention-to-treat analysis. However, the protocol or publication used six different descriptions for the intention-to-treat analysis, resulting in several important differences between the internal and published documents about the number of patients included in the analysis.
What Do These Findings Mean?
These findings from a sample of industry-sponsored trials on the off-label use of gabapentin suggest that when compared to the internal research reports, the trial publications did not always accurately reflect what was actually done in the trial. Therefore, the trial publication could not be considered to be an accurate and transparent record of the numbers of participants randomized and analyzed for efficacy. These findings support the need for further revisions of the CONSORT statement, such as including explicit statements about the criteria used to define each type of analysis and the numbers of participants excluded from each type of analysis. Further guidance is also needed to ensure consistent terminology for types of analysis. Of course, these revisions will improve reporting only if authors and journals adhere to them. These findings also highlight the need for all individual patient data to be made accessible to readers of the published article.
Additional Information
Please access these Web sites via the online version of this summary at
For more information, see the CONSORT statement website
The EQUATOR Network website is a resource center for the good reporting of health research studies and has more information about the SPIRIT initiative and the CONSORT statement
PMCID: PMC3558476  PMID: 23382656
9.  Strategies for prevention of postoperative delirium: a systematic review and meta-analysis of randomized trials 
Critical Care  2013;17(2):R47.
The ideal measures to prevent postoperative delirium remain unestablished. We conducted this systematic review and meta-analysis to clarify the significance of potential interventions.
The PRISMA statement guidelines were followed. Two researchers searched MEDLINE, EMBASE, CINAHL and the Cochrane Library for articles published in English before August 2012. Additional sources included reference lists from reviews and related articles from 'Google Scholar'. Randomized clinical trials (RCTs) on interventions seeking to prevent postoperative delirium in adult patients were included. Data extraction and methodological quality assessment were performed using predefined data fields and scoring system. Meta-analysis was accomplished for studies that used similar strategies. The primary outcome measure was the incidence of postoperative delirium. We further tested whether interventions effective in preventing postoperative delirium shortened the length of hospital stay.
We identified 38 RCTs with interventions ranging from perioperative managements to pharmacological, psychological or multicomponent interventions. Meta-analysis showed dexmedetomidine sedation was associated with less delirium compared to sedation produced by other drugs (two RCTs with 415 patients, pooled risk ratio (RR) = 0.39; 95% confidence interval (CI) = 0.16 to 0.95). Both typical (three RCTs with 965 patients, RR = 0.71; 95% CI = 0.54 to 0.93) and atypical antipsychotics (three RCTs with 627 patients, RR = 0.36; 95% CI = 0.26 to 0.50) decreased delirium occurrence when compared to placebos. Multicomponent interventions (two RCTs with 325 patients, RR = 0.71; 95% CI = 0.58 to 0.86) were effective in preventing delirium. No difference in the incidences of delirium was found between: neuraxial and general anesthesia (four RCTs with 511 patients, RR = 0.99; 95% CI = 0.65 to 1.50); epidural and intravenous analgesia (three RCTs with 167 patients, RR = 0.93; 95% CI = 0.61 to 1.43) or acetylcholinesterase inhibitors and placebo (four RCTs with 242 patients, RR = 0.95; 95% CI = 0.63 to 1.44). Effective prevention of postoperative delirium did not shorten the length of hospital stay (10 RCTs with 1,636 patients, pooled SMD (standard mean difference) = -0.06; 95% CI = -0.16 to 0.04).
The included studies showed great inconsistencies in definition, incidence, severity and duration of postoperative delirium. Meta-analysis supported dexmedetomidine sedation, multicomponent interventions and antipsychotics were useful in preventing postoperative delirium.
PMCID: PMC3672487  PMID: 23506796
10.  Limbal Stem Cell Transplantation 
Executive Summary
The objective of this analysis is to systematically review limbal stem cell transplantation (LSCT) for the treatment of patients with limbal stem cell deficiency (LSCD). This evidence-based analysis reviews LSCT as a primary treatment for nonpterygium LSCD conditions, and LSCT as an adjuvant therapy to excision for the treatment of pterygium.
Clinical Need: Condition and Target Population
The outer surface of the eye is covered by 2 distinct cell layers: the corneal epithelial layer that overlies the cornea, and the conjunctival epithelial layer that overlies the sclera. These cell types are separated by a transitional zone known as the limbus. The corneal epithelial cells are renewed every 3 to 10 days by a population of stem cells located in the limbus.
Nonpterygium Limbal Stem Cell Deficiency
When the limbal stem cells are depleted or destroyed, LSCD develops. In LSCD, the conjunctival epithelium migrates onto the cornea (a process called conjunctivalization), resulting in a thickened, irregular, unstable corneal surface that is prone to defects, ulceration, corneal scarring, vascularization, and opacity. Patients experience symptoms including severe irritation, discomfort, photophobia, tearing, blepharospasm, chronic inflammation and redness, and severely decreased vision.
Depending on the degree of limbal stem cell loss, LSCD may be total (diffuse) or partial (local). In total LSCD, the limbal stem cell population is completed destroyed and conjunctival epithelium covers the entire cornea. In partial LSCD, some areas of the limbus are unharmed, and the corresponding areas on the cornea maintain phenotypically normal corneal epithelium.
Confirmation of the presence of conjunctivalization is necessary for LSCD diagnosis as the other characteristics and symptoms are nonspecific and indicate a variety of diseases. The definitive test for LSCD is impression cytology, which detects the presence of conjunctival epithelium and its goblet cells on the cornea. However, in the opinion of a corneal expert, diagnosis is often based on clinical assessment, and in the expert’s opinion, it is unclear whether impression cytology is more accurate and reliable than clinical assessment, especially for patients with severe LSCD.
The incidence of LSCD is not well understood. A variety of underlying disorders are associated with LSCD including chemical or thermal injuries, ultraviolet and ionizing radiation, Stevens-Johnson syndrome, multiple surgeries or cryotherapies, contact lens wear, extensive microbial infection, advanced ocular cicatricial pemphigoid, and aniridia. In addition, some LSCD cases are idiopathic. These conditions are uncommon (e.g., the prevalence of aniridia ranges from 1 in 40,000 to 1 in 100,000 people).
Pterygium is a wing-shaped fibrovascular tissue growth from the conjunctiva onto the cornea. Pterygium is the result of partial LSCD caused by localized ultraviolet damage to limbal stem cells. As the pterygium invades the cornea, it may cause irregular astigmatism, loss of visual acuity, chronic irritation, recurrent inflammation, double vision, and impaired ocular motility.
Pterygium occurs worldwide. Incidence and prevalence rates are highest in the “pterygium belt,” which ranges from 30 degrees north to 30 degrees south of the equator, and lower prevalence rates are found at latitudes greater than 40 degrees. The prevalence of pterygium for Caucasians residing in urban, temperate climates is estimated at 1.2%.
Existing Treatments Other Than Technology Being Reviewed
Nonpterygium Limbal Stem Cell Deficiency
In total LSCD, a patient’s limbal stem cells are completely depleted, so any successful treatment must include new stem cells. Autologous oral mucosal epithelium transplantation has been proposed as an alternative to LSCT. However, this procedure is investigational, and there is very limited level 4c evidence1 to support this technique (fewer than 20 eyes examined in 4 case series and 1 case report).
For patients with partial LSCD, treatment may not be necessary if their visual axis is not affected. However, if the visual axis is conjunctivalized, several disease management options exist including repeated mechanical debridement of the abnormal epithelium; intensive, nonpreserved lubrication; bandage contact lenses; autologous serum eye drops; other investigational medical treatments; and transplantation of an amniotic membrane inlay. However, these are all disease management treatments; LSCT is the only curative option.
The primary treatment for pterygium is surgical excision. However, recurrence is a common problem after excision using the bare sclera technique: reported recurrence rates range from 24% to 89%. Thus, a variety of adjuvant therapies have been used to reduce the risk of pterygium recurrence including LSCT, amniotic membrane transplantation (AMT), conjunctival autologous (CAU) transplantation, and mitomycin C (MMC, an antimetabolite drug).
New Technology Being Reviewed
To successfully treat LSCD, the limbal stem cell population must be repopulated. To achieve this, 4 LSCT procedures have been developed: conjunctival-limbal autologous (CLAU) transplantation; living-related conjunctival-limbal allogeneic (lr-CLAL) transplantation; keratolimbal allogeneic (KLAL) transplantation; and ex vivo expansion of limbal stem cells transplantation. Since the ex vivo expansion of limbal stem cells transplantation procedure is considered experimental, it has been excluded from the systematic review. These procedures vary by the source of donor cells and the amount of limbal tissue used. For CLAU transplants, limbal stem cells are obtained from the patient’s healthy eye. For lr-CLAL and KLAL transplants, stem cells are obtained from living-related and cadaveric donor eyes, respectively.
In CLAU and lr-CLAL transplants, 2 to 4 limbal grafts are removed from the superior and inferior limbus of the donor eye. In KLAL transplants, the entire limbus from the donor eye is used.
The recipient eye is prepared by removing the abnormal conjunctival and scar tissue. An incision is made into the conjunctival tissue into which the graft is placed, and the graft is then secured to the neighbouring limbal and scleral tissue with sutures. Some LSCT protocols include concurrent transplantation of an amniotic membrane onto the cornea.
Regulatory Status
Health Canada does not require premarket licensure for stem cells. However, they are subject to Health Canada’s clinical trial regulations until the procedure is considered accepted transplantation practice, at which time it will be covered by the Safety of Human Cells, Tissues and Organs for Transplantation Regulations (CTO Regulations).
Review Strategy
The Medical Advisory Secretariat systematically reviewed the literature to assess the effectiveness and safety of LSCT for the treatment of patients with nonpterygium LSCD and pterygium. A comprehensive search method was used to retrieve English-language journal articles from selected databases.
The GRADE approach was used to systematically and explicitly evaluate the quality of evidence and strength of recommendations.
Summary of Findings
Nonpterygium Limbal Stem Cell Deficiency
The search identified 873 citations published between January 1, 2000, and March 31, 2008. Nine studies met the inclusion criteria, and 1 additional citation was identified through a bibliography review. The review included 10 case series (3 prospective and 7 retrospective).
Patients who received autologous transplants (i.e., CLAU) achieved significantly better long-term corneal surface results compared with patients who received allogeneic transplants (lr-CLAL, P< .001; KLAL, P< .001). There was no significant difference in corneal surface outcomes between the allogeneic transplant options, lr-CLAL and KLAL (P = .328). However, human leukocyte antigen matching and systemic immunosuppression may improve the outcome of lr-CLAL compared with KLAL. Regardless of graft type, patients with Stevens-Johnson syndrome had poorer long-term corneal surface outcomes.
Concurrent AMT was associated with poorer long-term corneal surface improvements. When the effect of the AMT was removed, the difference between autologous and allogeneic transplants was much smaller.
Patients who received CLAU transplants had a significantly higher rate of visual acuity improvements compared with those who received lr-CLAL transplants (P = .002). However, to achieve adequate improvements in vision, patients with deep corneal scarring will require a corneal transplant several months after the LSCT.
No donor eye complications were observed.
Epithelial rejection and microbial keratitis were the most common long-term complications associated with LSCT (complications occurred in 6%–15% of transplantations). These complications can result in graft failure, so patients should be monitored regularly following LSCT.
The search yielded 152 citations published between January 1, 2000 and May 16, 2008. Six randomized controlled trials (RCTs) that evaluated LSCT as an adjuvant therapy for the treatment of pterygium met the inclusion criteria and were included in the review.
Limbal stem cell transplantation was compared with CAU, AMT, and MMC. The results showed that CLAU significantly reduced the risk of pterygium recurrence compared with CAU (relative risk [RR], 0.09; 95% confidence interval [CI], 0.01–0.69; P = .02). CLAU reduced the risk of pterygium recurrence for primary pterygium compared with MMC, but this comparison did not reach statistical significance (RR, 0.48; 95% CI, 0.21–1.10; P = .08). Both AMT and CLAU had similar low rates of recurrence (2 recurrences in 43 patients and 4 in 46, respectively), and the RR was not significant (RR, 1.88; 95% CI, 0.37–9.5; P = .45). Since sample sizes in the included studies were small, failure to detect a significant difference between LSCT and AMT or MMC could be the result of type II error. Limbal stem cell transplantation as an adjuvant to excision is a relatively safe procedure as long-term complications were rare (< 2%).
GRADE Quality of Evidence
Nonpterygium Limbal Stem Cell Deficiency
The evidence for the analyses related to nonpterygium LSCD was based on 3 prospective and 7 retrospective case series. Thus, the GRADE quality of evidence is very low, and any estimate of effect is very uncertain.
The analyses examining LSCT as an adjuvant treatment option for pterygium were based on 6 RCTs. The quality of evidence for the overall body of evidence for each treatment option comparison was assessed using the GRADE approach. In each of the comparisons, the quality of evidence was downgraded due to serious or very serious limitations in study quality (individual study quality was assessed using the Jadad scale, and an assessment of allocation concealment and the degree of loss to follow-up), which resulted in low- to moderate-quality GRADE evidence ratings (low-quality evidence for the CLAU and AMT and CLAU and MMC comparisons, and moderate-quality evidence for the CLAU and CAU comparison).
Ontario Health System Impact Analysis
Nonpterygium Limbal Stem Cell Deficiency
Since 1999, Ontario’s out-of-country (OOC) program has approved and reimbursed 8 patients for LSCTs and 1 patient for LSCT consultations. Similarly, most Canadian provinces have covered OOC or out-of-province LSCTs. Several corneal experts in Ontario have the expertise to perform LSCTs.
As there are no standard guidelines for LSCT, patients who receive transplants OOC may not receive care aligned with the best evidence. To date, many of the patients from Ontario who received OOC LSCTs received concurrent AMTs, and the evidence from this analysis questions the use of this procedure. In addition, 1 patient received a cultured LSCT, a procedure that is considered investigational. Many patients with LSCD have bilateral disease and therefore require allogeneic transplants. These patients will require systemic and topical immunosuppression for several years after the transplant, perhaps indefinitely. Thus, systemic side effects associated with immunosuppression are a potential concern, and patients must be monitored regularly.
Amniotic membrane transplantation is a common addition to many ocular surface reconstruction procedures, including LSCT. Amniotic membranes are recovered from human placentas from planned, uneventful caesarean sections. Before use, serological screening of the donor’s blood should be conducted. However, there is still a theoretical risk of disease transmission associated with this procedure.
Financial Impact
For the patients who were reimbursed for OOC LSCTs, the average cost of LSCT per eye was $18,735.20 Cdn (range, $8,219.54–$33,933.32). However, the actual cost per patient is much higher as these costs do not include consultations and follow-up visits, multiple LSCTs, and any additional procedures (e.g., corneal transplants) received during the course of treatment OOC. When these additional costs were considered, the average cost per patient was $57,583 Cdn (range, $8,219.54–$130,628.20).
The estimated average total cost per patient for performing LSCT in Ontario is $2,291.48 Cdn (range, $951.48–$4,538.48) including hospital and physician fees. This cost is based on the assumption that LSCT is technically similar to a corneal transplant, an assumption which needs to be verified. The cost does not include corneal transplantations, which some proportion of patients receiving a LSCT will require within several months of the limbal transplant.
Pterygium recurrence rates after surgical excision are high, ranging from 24% to 89%. However, according to clinical experts, the rate of recurrence is low in Ontario. While there is evidence that the prevalence of pterygium is higher in the “pterygium belt,” there was no evidence to suggest different recurrence rates or disease severity by location or climate.
Nonpterygium Limbal Stem Cell Deficiency
Successful LSCTs result in corneal re-epithelialization and improved vision in patients with LSCD. However, patients who received concurrent AMT had poorer long-term corneal surface improvements. Conjunctival-limbal autologous transplantation is the treatment option of choice, but if it is not possible, living-related or cadaveric allogeneic transplants can be used. The benefits of LSCT outweigh the risks and burdens, as shown in Executive Summary Table 1. According to GRADE, these recommendations are strong with low- to very low-quality evidence.
Benefits, Risks, and Burdens – Nonpterygium Limbal Stem Cell Deficiency
Short- and long-term improvement in corneal surface (stable, normal corneal epithelium and decreased vascularization and opacity)
Improvement in vision (visual acuity and functional vision)
Long-term complications are experienced by 8% to 16% of patients
Risks associated with long-term immunosuppression for recipients of allogeneic grafts
Potential risk of induced LSCD in donor eyes
High cost of treatment (average cost per patient via OOC program is $57,583; estimated cost of procedure in Ontario is $2,291.48)
Costs are expressed in Canadian dollars.
GRADE of recommendation: Strong recommendation, low-quality or very low-quality evidence
benefits clearly outweigh risks and burdens
case series studies
strong, but may change if higher-quality evidence becomes available
Conjunctival-limbal autologous transplantations significantly reduced the risk of pterygium recurrence compared with CAU. No other comparison yielded statistically significant results, but CLAU reduced the risk of recurrence compared with MMC. However, the benefit of LSCT in Ontario is uncertain as the severity and recurrence of pterygium in Ontario is unknown. The complication rates suggest that CLAU is a safe treatment option to prevent the recurrence of pterygium. According to GRADE, given the balance of the benefits, risks, and burdens, the recommendations are very weak with moderate quality evidence, as shown in Executive Summary Table 2.
Benefits, Risks, and Burdens – Pterygium
Reduced recurrence; however, if recurrence is low in Ontario, this benefit might be minimal
Long-term complications rare
Increased cost
GRADE of recommendation: Very weak recommendations, moderate quality evidence.
uncertainty in the estimates of benefits, risks, and burden; benefits, risks, and burden may be closely balanced
very weak, other alternatives may be equally reasonable
PMCID: PMC3377549  PMID: 23074512
11.  Ultraviolet Phototherapy Management of Moderate-to-Severe Plaque Psoriasis 
Executive Summary
The purpose of this evidence based analysis was to determine the effectiveness and safety of ultraviolet phototherapy for moderate-to-severe plaque psoriasis.
Research Questions
The specific research questions for the evidence review were as follows:
What is the safety of ultraviolet phototherapy for moderate-to-severe plaque psoriasis?
What is the effectiveness of ultraviolet phototherapy for moderate-to-severe plaque psoriasis?
Clinical Need: Target Population and Condition
Psoriasis is a common chronic, systemic inflammatory disease affecting the skin, nails and occasionally the joints and has a lifelong waning and waxing course. It has a worldwide occurrence with a prevalence of at least 2% of the general population, making it one of the most common systemic inflammatory diseases. The immune-mediated disease has several clinical presentations with the most common (85% - 90%) being plaque psoriasis.
Characteristic features of psoriasis include scaling, redness, and elevation of the skin. Patients with psoriasis may also present with a range of disabling symptoms such as pruritus (itching), pain, bleeding, or burning associated with plaque lesions and up to 30% are classified as having moderate-to-severe disease. Further, some psoriasis patients can be complex medical cases in which diabetes, inflammatory bowel disease, and hypertension are more likely to be present than in control populations and 10% also suffer from arthritis (psoriatic arthritis). The etiology of psoriasis is unknown but is thought to result from complex interactions between the environment and predisposing genes.
Management of psoriasis is related to the extent of the skin involvement, although its presence on the hands, feet, face or genitalia can present challenges. Moderate-to-severe psoriasis is managed by phototherapy and a range of systemic agents including traditional immunosuppressants such as methotrexate and cyclospsorin. Treatment with modern immunosuppressant agents known as biologicals, which more specifically target the immune defects of the disease, is usually reserved for patients with contraindications and those failing or unresponsive to treatments with traditional immunosuppressants or phototherapy.
Treatment plans are based on a long-term approach to managing the disease, patient’s expectations, individual responses and risk of complications. The treatment goals are several fold but primarily to:
1) improve physical signs and secondary psychological effects,
2) reduce inflammation and control skin shedding,
3) control physical signs as long as possible, and to
4) avoid factors that can aggravate the condition.
Approaches are generally individualized because of the variable presentation, quality of life implications, co-existent medical conditions, and triggering factors (e.g. stress, infections and medications). Individual responses and commitments to therapy also present possible limitations.
Ultraviolet phototherapy units have been licensed since February 1993 as a class 2 device in Canada. Units are available as hand held devices, hand and foot devices, full-body panel, and booth styles for institutional and home use. Units are also available with a range of ultraviolet A, broad and narrow band ultraviolet B (BB-UVB and NB-UVB) lamps. After establishing appropriate ultraviolet doses, three-times weekly treatment schedules for 20 to 25 treatments are generally needed to control symptoms.
Evidence-Based Analysis Methods
The literature search strategy employed keywords and subject headings to capture the concepts of 1) phototherapy and 2) psoriasis. The search involved runs in the following databases: Ovid MEDLINE (1996 to March Week 3 2009), OVID MEDLINE In-Process and Other Non-Indexed Citations, EMBASE (1980 to 2009 Week 13), the Wiley Cochrane Library, and the Centre for Reviews and Dissemination/International Agency for Health Technology Assessment. Parallel search strategies were developed for the remaining databases. Search results were limited to human and English-language published between January 1999 and March 31, 2009. Search alerts were generated and reviewed for relevant literature up until May 31, 2009.
English language reports and human studies
Ultraviolet phototherapy interventions for plaque-type psoriasis
Reports involving efficacy and/or safety outcome studies
Original reports with defined study methodology
Standardized measurements on outcome events such as technical success, safety, effectiveness, durability, quality of life or patient satisfaction
Non-systematic reviews, letters, comments and editorials
Randomized trials involving side-to-side or half body comparisons
Randomized trials not involving ultraviolet phototherapy intervention for plaque-type psoriasis
Trials involving dosing studies, pilot feasibility studies or lacking control groups
Summary of Findings
A 2000 health technology evidence report on the overall management of psoriasis by The National Institute Health Research (NIHR) Health Technology Assessment Program of the UK was identified in the MAS evidence-based review. The report included 109 RCT studies published between 1966 and June 1999 involving four major treatment approaches – 51 on phototherapy, 32 on oral retinoids, 18 on cyclosporin and five on fumarates.. The absence of RCTs on methotrexate was noted as original studies with this agent had been performed prior to 1966.
Of the 51 RCT studies involving phototherapy, 22 involved UVA, 21 involved UVB, five involved both UVA and UVB and three involved natural light as a source of UV. The RCT studies included comparisons of treatment schedules, ultraviolet source, addition of adjuvant therapies, and comparisons between phototherapy and topical treatment schedules. Because of heterogeneity, no synthesis or meta-analysis could be performed. Overall, the reviewers concluded that the efficacy of only five therapies could be supported from the RCT-based evidence review: photochemotherapy or phototherapy, cyclosporin, systemic retinoids, combination topical vitamin D3 analogues (calcipotriol) and corticosteroids in combination with phototherapy and fumarates. Although there was no RCT evidence supporting methotrexate, it’s efficacy for psoriasis is well known and it continues to be a treatment mainstay.
The conclusion of the NIHR evidence review was that both photochemotherapy and phototherapy were effective treatments for clearing psoriasis, although their comparative effectiveness was unknown. Despite the conclusions on efficacy, a number of issues were identified in the evidence review and several areas for future research were discussed to address these limitations. Trials focusing on comparative effectiveness, either between ultraviolet sources or between classes of treatment such as methotrexate versus phototherapy, were recommended to refine treatment algorithms. The need for better assessment of cost-effectiveness of therapies to consider systemic drug costs and costs of surveillance, as well as drug efficacy, were also noted. Overall, the authors concluded that phototherapy and photochemotherapy had important roles in psoriasis management and were standard therapeutic options for psoriasis offered in dermatology practices.
The MAS evidence-based review focusing on the RCT trial evidence for ultraviolet phototherapy management of moderate-to-severe plaque psoriasis was performed as an update to the NIHR 2000 systemic review on treatments for severe psoriasis. In this review, an additional 26 RCT reports examining phototherapy or photochemotherapy for psoriasis were identified. Among the studies were two RCTs comparing ultraviolet wavelength sources, five RCTs comparing different forms of phototherapy, four RCTs combining phototherapy with prior spa saline bathing, nine RCTs combining phototherapy with topical agents, two RCTs combining phototherapy with the systemic immunosuppressive agents methotrexate or alefacept, one RCT comparing phototherapy with an additional light source (the excimer laser), and one comparing a combination therapy with phototherapy and psychological intervention involving simultaneous audiotape sessions on mindfulness and stress reduction. Two trials also examined the effect of treatment setting on effectiveness of phototherapy, one on inpatient versus outpatient therapy and one on outpatient clinic versus home-based phototherapy.
The conclusions of the MAS evidence-based review are outlined in Table ES1. In summary, phototherapy provides good control of clinical symptoms in the short term for patients with moderate-to-severe plaque-type psoriasis that have failed or are unresponsive to management with topical agents. However, many of the evidence gaps identified in the NIHR 2000 evidence review on psoriasis management persisted. In particular, the lack of evidence on the comparative effectiveness and/or cost-effectiveness between the major treatment options for moderate-to-severe psoriasis remained. The evidence on effectiveness and safety of longer term strategies for disease management has also not been addressed. Evidence for the safety, effectiveness, or cost-effectiveness of phototherapy delivered in various settings is emerging but is limited. In addition, because all available treatments for psoriasis – a disease with a high prevalence, chronicity, and cost – are palliative rather than curative, strategies for disease control and improvements in self-efficacy employed in other chronic disease management strategies should be investigated.
RCT Evidence for Ultraviolet Phototherapy Treatment of Moderate-To-Severe Plaque Psoriasis
Phototherapy is an effective treatment for moderate-to-severe plaque psoriasis
Narrow band PT is more effective than broad band PT for moderate-to-severe plaque psoriasis
Oral-PUVA has a greater clinical response, requires less treatments and has a greater cumulative UV irradiation dose than UVB to achieve treatment effects for moderate-to-severe plaque psoriasis
Spa salt water baths prior to phototherapy did increase short term clinical response of moderate-to-severe plaque psoriasis but did not decrease cumulative UV irradiation dose
Addition of topical agents (vitamin D3 calcipotriol) to NB-UVB did not increase mean clinical response or decrease treatments or cumulative UV irradiation dose
Methotrexate prior to NB-UVB in high need psoriasis patients did significantly increase clinical response, decrease number of treatment sessions and decrease cumulative UV irradiation dose
Phototherapy following alefacept did increase early clinical response in moderate-to-severe plaque psoriasis
Effectiveness and safety of home NB-UVB phototherapy was not inferior to NB-UVB phototherapy provided in a clinic to patients with psoriasis referred for phototherapy. Treatment burden was lower and patient satisfaction was higher with home therapy and patients in both groups preferred future phototherapy treatments at home
Ontario Health System Considerations
A 2006 survey of ultraviolet phototherapy services in Canada identified 26 phototherapy clinics in Ontario for a population of over 12 million. At that time, there were 177 dermatologists and 50 geographic regions in which 28% (14/50) provided phototherapy services. The majority of the phototherapy services were reported to be located in densely populated areas; relatively few patients living in rural communities had access to these services. The inconvenience of multiple weekly visits for optimal phototherapy treatment effects poses additional burdens to those with travel difficulties related to health, job, or family-related responsibilities.
Physician OHIP billing for phototherapy services totaled 117,216 billings in 2007, representing approximately 1,800 patients in the province treated in private clinics. The number of patients treated in hospitals is difficult to estimate as physician costs are not billed directly to OHIP in this setting. Instead, phototherapy units and services provided in hospitals are funded by hospitals’ global budgets. Some hospitals in the province, however, have divested their phototherapy services, so the number of phototherapy clinics and their total capacity is currently unknown.
Technological advances have enabled changes in phototherapy treatment regimens from lengthy hospital inpatient stays to outpatient clinic visits and, more recently, to an at-home basis. When combined with a telemedicine follow-up, home phototherapy may provide an alternative strategy for improved access to service and follow-up care, particularly for those with geographic or mobility barriers. Safety and effectiveness have, however, so far been evaluated for only one phototherapy home-based delivery model. Alternate care models and settings could potentially increase service options and access, but the broader consequences of the varying cost structures and incentives that either increase or decrease phototherapy services are unknown.
Economic Analyses
The focus of the current economic analysis was to characterize the costs associated with the provision of NB-UVB phototherapy for plaque-type, moderate-to-severe psoriasis in different clinical settings, including home therapy. A literature review was conducted and no cost-effectiveness (cost-utility) economic analyses were published in this area.
Hospital, Clinic, and Home Costs of Phototherapy
Costs for NB-UVB phototherapy were based on consultations with equipment manufacturers and dermatologists. Device costs applicable to the provision of NB-UVB phototherapy in hospitals, private clinics and at a patient’s home were estimated. These costs included capital costs of purchasing NB-UVB devices (amortized over 15-20 years), maintenance costs of replacing equipment bulbs, physician costs of phototherapy treatment in private clinics ($7.85 per phototherapy treatment), and medication and laboratory costs associated with treatment of moderate-to-severe psoriasis.
NB-UVB phototherapy services provided in a hospital setting were paid for by hospitals directly. Phototherapy services in private clinic and home settings were paid for by the clinic and patient, respectively, except for physician services covered by OHIP. Indirect funding was provided to hospitals as part of global budgeting and resource allocation. Home therapy services for NB-UVB phototherapy were not covered by the MOHLTC. Coverage for home-based phototherapy however, was in some cases provided by third party insurers.
Device costs for NB-UVB phototherapy were estimated for two types of phototherapy units: a “booth unit” consisting of 48 bulbs used in hospitals and clinics, and a “panel unit” consisting of 10 bulbs for home use. The device costs of the booth and panel units were estimated at approximately $18,600 and $2,900, respectively; simple amortization over 15 and 20 years implied yearly costs of approximately $2,500 and $150, respectively. Replacement cost for individual bulbs was about $120 resulting in total annual cost of maintenance of about $8,640 and $120 for booth and panel units, respectively.
Estimated Total Costs for Ontario
Average annual cost per patient for NB-UVB phototherapy provided in the hospital, private clinic or at home was estimated to be $292, $810 and $365 respectively. For comparison purposes, treatment of moderate-to-severe psoriasis with methotrexate and cyclosporin amounted to $712 and $3,407 annually per patient respectively; yearly costs for biological drugs were estimated to be $18,700 for alefacept and $20,300 for etanercept-based treatments.
Total annual costs of NB-UVB phototherapy were estimated by applying average costs to an estimated proportion of the population (age 18 or older) eligible for phototherapy treatment. The prevalence of psoriasis was estimated to be approximately 2% of the population, of which about 85% was of plaque-type psoriasis and approximately 20% to 30% was considered moderate-to-severe in disease severity. An estimate of 25% for moderate-to-severe psoriasis cases was used in the current economic analysis resulting in a range of 29,400 to 44,200 cases. Approximately 21% of these patients were estimated to be using NB-UVB phototherapy for treatment resulting in a number of cases in the range between 6,200 and 9,300 cases. The average (7,700) number of cases was used to calculate associated costs for Ontario by treatment setting.
Total annual costs were as follows: $2.3 million in a hospital setting, $6.3 million in a private clinic setting, and $2.8 million for home phototherapy. Costs for phototherapy services provided in private clinics were greater ($810 per patient annually; total of $6.3 million annually) and differed from the same services provided in the hospital setting only in terms of additional physician costs associated with phototherapy OHIP fees.
Psoriasis, ultraviolet radiation, phototherapy, photochemotherapy, NB-UVB, BB-UVB PUVA
PMCID: PMC3377497  PMID: 23074532
12.  Expanding Disease Definitions in Guidelines and Expert Panel Ties to Industry: A Cross-sectional Study of Common Conditions in the United States 
PLoS Medicine  2013;10(8):e1001500.
Financial ties between health professionals and industry may unduly influence professional judgments and some researchers have suggested that widening disease definitions may be one driver of over-diagnosis, bringing potentially unnecessary labeling and harm. We aimed to identify guidelines in which disease definitions were changed, to assess whether any proposed changes would increase the numbers of individuals considered to have the disease, whether potential harms of expanding disease definitions were investigated, and the extent of members' industry ties.
Methods and Findings
We undertook a cross-sectional study of the most recent publication between 2000 and 2013 from national and international guideline panels making decisions about definitions or diagnostic criteria for common conditions in the United States. We assessed whether proposed changes widened or narrowed disease definitions, rationales offered, mention of potential harms of those changes, and the nature and extent of disclosed ties between members and pharmaceutical or device companies.
Of 16 publications on 14 common conditions, ten proposed changes widening and one narrowing definitions. For five, impact was unclear. Widening fell into three categories: creating “pre-disease”; lowering diagnostic thresholds; and proposing earlier or different diagnostic methods. Rationales included standardising diagnostic criteria and new evidence about risks for people previously considered to not have the disease. No publication included rigorous assessment of potential harms of proposed changes.
Among 14 panels with disclosures, the average proportion of members with industry ties was 75%. Twelve were chaired by people with ties. For members with ties, the median number of companies to which they had ties was seven. Companies with ties to the highest proportions of members were active in the relevant therapeutic area. Limitations arise from reliance on only disclosed ties, and exclusion of conditions too broad to enable analysis of single panel publications.
For the common conditions studied, a majority of panels proposed changes to disease definitions that increased the number of individuals considered to have the disease, none reported rigorous assessment of potential harms of that widening, and most had a majority of members disclosing financial ties to pharmaceutical companies.
Please see later in the article for the Editors' Summary
Editors' Summary
Health professionals generally base their diagnosis of physical and mental disorders among their patients on disease definitions and diagnostic thresholds that are drawn up by expert panels and published as statements or as part of clinical practice guidelines. These disease definitions and diagnostic thresholds are reviewed and updated in response to changes in disease detection methods, treatments, medical knowledge, and, in the case of mental illness, changes in cultural norms. Sometimes, the review process widens disease definitions and lowers diagnostic thresholds. Such changes can be beneficial. For example, they might ensure that life-threatening conditions are diagnosed early when they are still treatable. But the widening of disease definitions can also lead to over-diagnosis—the diagnosis of a condition in a healthy individual that will never cause any symptoms and won't lead to an early death. Over-diagnosis can unnecessarily label people as ill, harm healthy individuals by exposing them to treatments they do not need, and waste resources that could be used to treat or prevent “genuine” illness.
Why Was This Study Done?
In recent years, evidence for widespread financial and non-financial ties between pharmaceutical companies and the health professionals involved in writing clinical practice guidelines has increased, and concern that these links may influence professional judgments has grown. As a result, a 2011 report from the US Institute of Medicine (IOM) recommended that, whenever possible, guideline developers should not have conflicts of interest, that a minority of the panel members involved in guideline development should have conflicts of interest, and that the chairs of these panels should be free of conflicts. Much less is known, however, about the ties between industry and the health professionals involved in reviewing disease definitions and whether these ties might in some way contribute to over-diagnosis. In this cross-sectional study (an investigation that takes a snapshot of a situation at a single time point), the researchers identify panels that have recently made decisions about definitions or diagnostic thresholds for conditions that are common in the US and describe the industry ties among the panel members and the changes in disease definitions proposed by the panels.
What Did the Researchers Do and Find?
The researchers identified 16 publications in which expert panels proposed changes to the disease definitions and diagnostic criteria for 14 conditions that are common in the US such as hypertension (high blood pressure) and Alzheimer disease. The proposed changes widened the disease definition for ten diseases, narrowed it for one disease, and had an unclear impact for five diseases. Reasons included in the publications for changing disease definitions included new evidence of risk for people previously considered normal (pre-hypertension) and the emergence of new biomarkers, tests, or treatments (Alzheimer disease). Only six of the panels mentioned possible harms of the proposed changes and none appeared to rigorously assess the downsides of expanding definitions. Of the 15 panels involved in the publications (one panel produced two publications), 12 included members who disclosed financial ties to multiple companies. Notably, the commonest industrial ties among these panels were to companies marketing drugs for the disease being considered by that panel. On average, 75% of panel members disclosed industry ties (range 0% to 100%) to a median of seven companies each. Moreover, similar proportions of panel members disclosed industry ties in publications released before and after the 2011 IOM report.
What Do These Findings Mean?
These findings show that, for the conditions studied, most panels considering disease definitions and diagnostic criteria proposed changes that widened disease definitions and that financial ties with pharmaceutical companies with direct interests in the therapeutic area covered by the panel were common among panel members. Because this study does not include a comparison group, these findings do not establish a causal link between industry ties and proposals to change disease definitions. Moreover, because the study concentrates on a subset of common diseases in the US setting, the generalizability of these findings is limited. Despite these and other study limitations, these findings provide new information about the ties between industry and influential medical professionals and raise questions about the current processes of disease definition. Future research, the researchers suggest, should investigate how disease definitions change over time, how much money panel members receive from industry, and how panel proposals affect the potential market of sponsors. Finally it should aim to design new processes for reviewing disease definitions that are free from potential conflicts of interest.
Additional Information
Please access these Web sites via the online version of this summary at
A PLOS Medicine Research Article by Knüppel et al. assesses the representation of ethical issues in general clinical practice guidelines on dementia care
Wikipedia has a page on medical diagnosis (note: Wikipedia is a free online encyclopedia that anyone can edit; available in several languages)
An article on over-diagnosis by two of the study authors is available; an international conference on preventing over-diagnosis will take place this September
The 2011 US Institute of Medicine report Clinical Practice Guidelines We Can Trust is available
A PLOS Medicine Essay by Lisa Cosgrove and Sheldon Krimsky discusses the financial ties with industry of panel members involved in the preparation of the latest revision of the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders (DSM), which provides standard criteria for the classification of mental disorders
PMCID: PMC3742441  PMID: 23966841
13.  Factors Associated with Findings of Published Trials of Drug–Drug Comparisons: Why Some Statins Appear More Efficacious than Others 
PLoS Medicine  2007;4(6):e184.
Published pharmaceutical industry–sponsored trials are more likely than non-industry-sponsored trials to report results and conclusions that favor drug over placebo. Little is known about potential biases in drug–drug comparisons. This study examined associations between research funding source, study design characteristics aimed at reducing bias, and other factors that potentially influence results and conclusions in randomized controlled trials (RCTs) of statin–drug comparisons.
Methods and Findings
This is a cross-sectional study of 192 published RCTs comparing a statin drug to another statin drug or non-statin drug. Data on concealment of allocation, selection bias, blinding, sample size, disclosed funding source, financial ties of authors, results for primary outcomes, and author conclusions were extracted by two coders (weighted kappa 0.80 to 0.97). Univariate and multivariate logistic regression identified associations between independent variables and favorable results and conclusions. Of the RCTs, 50% (95/192) were funded by industry, and 37% (70/192) did not disclose any funding source. Looking at the totality of available evidence, we found that almost all studies (98%, 189/192) used only surrogate outcome measures. Moreover, study design weaknesses common to published statin–drug comparisons included inadequate blinding, lack of concealment of allocation, poor follow-up, and lack of intention-to-treat analyses. In multivariate analysis of the full sample, trials with adequate blinding were less likely to report results favoring the test drug, and sample size was associated with favorable conclusions when controlling for other factors. In multivariate analysis of industry-funded RCTs, funding from the test drug company was associated with results (odds ratio = 20.16 [95% confidence interval 4.37–92.98], p < 0.001) and conclusions (odds ratio = 34.55 [95% confidence interval 7.09–168.4], p < 0.001) that favor the test drug when controlling for other factors. Studies with adequate blinding were less likely to report statistically significant results favoring the test drug.
RCTs of head-to-head comparisons of statins with other drugs are more likely to report results and conclusions favoring the sponsor's product compared to the comparator drug. This bias in drug–drug comparison trials should be considered when making decisions regarding drug choice.
Lisa Bero and colleagues found published trials comparing one statin with another were more likely to report results and conclusions favoring the sponsor's product than the comparison drug.
Editors' Summary
Randomized controlled trials are generally considered to be the most reliable type of experimental study for evaluating the effectiveness of different treatments. Randomization involves the assignment of participants in the trial to different treatment groups by the play of chance. Properly done, this procedure means that the different groups are comparable at outset, reducing the chance that outside factors could be responsible for treatment effects seen in the trial. When done properly, randomization also ensures that the clinicians recruiting participants into the trial cannot know the treatment group to which a patient will end up being assigned. However, despite these advantages, a large number of factors can still result in bias creeping in. Bias comes about when the findings of research appear to differ in some systematic way from the true result. Other research studies have suggested that funding is a source of bias; studies sponsored by drug companies seem to more often favor the sponsor's drug than trials not sponsored by drug companies
Why Was This Study Done?
The researchers wanted to more precisely understand the impact of different possible sources of bias in the findings of randomized controlled trials. In particular, they wanted to study the outcomes of “head-to-head” drug comparison studies for one particular class of drugs, the statins. Drugs in this class are commonly prescribed to reduce the levels of cholesterol in blood amongst people who are at risk of heart and other types of disease. This drug class is a good example for studying the role of bias in drug–drug comparison trials, because these trials are extensively used in decision making by health-policy makers.
What Did the Researchers Do and Find?
This research study was based on searching PubMed, a biomedical literature database, with the aim of finding all randomized controlled trials of statins carried out between January 1999 and May 2005 (reference lists also were searched). Only trials which compared one statin to another statin or one statin to another type of drug were included. The researchers extracted the following information from each article: the study's source of funding, aspects of study design, the overall results, and the authors' conclusions. The results were categorized to show whether the findings were favorable to the test drug (the newer statin), inconclusive, or not favorable to the test drug. Aspects of each study's design were also categorized in relation to various features, such as how well the randomization was done (in particular, the degree to which the processes used would have prevented physicians from knowing which treatment a patient was likely to receive on enrollment); whether all participants enrolled in the trial were eventually analyzed; and whether investigators or participants knew what treatment an individual was receiving.
One hundred and ninety-two trials were included in this study, and of these, 95 declared drug company funding; 23 declared government or other nonprofit funding while 74 did not declare funding or were not funded. Trials that were properly blinded (where participants and investigators did not know what treatment an individual received) were less likely to have conclusions favoring the test drug. However, large trials were more likely to favor the test drug than smaller trials. When looking specifically at the trials funded by drug companies, the researchers found various factors that predicted whether a result or conclusion favored the test drug. These included the impact of the journal publishing the results; the size of the trial; and whether funding came from the maker of the test drug. However, properly blinded trials were less likely to produce results favoring the test drug. Even once all other factors were accounted for, the funding source for the study was still linked with results and conclusions that favored the maker of the test drug.
What Do These Findings Mean?
This study shows that the type of sponsorship available for randomized controlled trials of statins was strongly linked to the results and conclusions of those studies, even when other factors were taken into account. However, it is not clear from this study why sponsorship has such a strong link to the overall findings. There are many possible reasons why this might be. Some people have suggested that drug companies may deliberately choose lower dosages for the comparison drug when they carry out “head-to-head” trials; this tactic is likely to result in the company's product doing better in the trial. Others have suggested that trials which produce unfavorable results are not published, or that unfavorable outcomes are suppressed. Whatever the reasons for these findings, the implications are important, and suggest that the evidence base relating to statins may be substantially biased.
Additional Information.
Please access these Web sites via the online version of this summary at
The James Lind Library has been created to help people understand fair tests of treatments in health care by illustrating how fair tests have developed over the centuries
The International Committee of Medical Journal Editors has provided guidance regarding sponsorship, authorship, and accountability
The CONSORT statement is a research tool that provides an evidence-based approach for reporting the results of randomized controlled trials
Good Publication Practice guidelines provide standards for responsible publication of research sponsored by pharmaceutical companies
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PMCID: PMC1885451  PMID: 17550302
14.  Point-of-Care International Normalized Ratio (INR) Monitoring Devices for Patients on Long-term Oral Anticoagulation Therapy 
Executive Summary
Subject of the Evidence-Based Analysis
The purpose of this evidence based analysis report is to examine the safety and effectiveness of point-of-care (POC) international normalized ratio (INR) monitoring devices for patients on long-term oral anticoagulation therapy (OAT).
Clinical Need: Target Population and Condition
Long-term OAT is typically required by patients with mechanical heart valves, chronic atrial fibrillation, venous thromboembolism, myocardial infarction, stroke, and/or peripheral arterial occlusion. It is estimated that approximately 1% of the population receives anticoagulation treatment and, by applying this value to Ontario, there are an estimated 132,000 patients on OAT in the province, a figure that is expected to increase with the aging population.
Patients on OAT are regularly monitored and their medications adjusted to ensure that their INR scores remain in the therapeutic range. This can be challenging due to the narrow therapeutic window of warfarin and variation in individual responses. Optimal INR scores depend on the underlying indication for treatment and patient level characteristics, but for most patients the therapeutic range is an INR score of between 2.0 and 3.0.
The current standard of care in Ontario for patients on long-term OAT is laboratory-based INR determination with management carried out by primary care physicians or anticoagulation clinics (ACCs). Patients also regularly visit a hospital or community-based facility to provide a venous blood samples (venipuncture) that are then sent to a laboratory for INR analysis.
Experts, however, have commented that there may be under-utilization of OAT due to patient factors, physician factors, or regional practice variations and that sub-optimal patient management may also occur. There is currently no population-based Ontario data to permit the assessment of patient care, but recent systematic reviews have estimated that less that 50% of patients receive OAT on a routine basis and that patients are in the therapeutic range only 64% of the time.
Overview of POC INR Devices
POC INR devices offer an alternative to laboratory-based testing and venipuncture, enabling INR determination from a fingerstick sample of whole blood. Independent evaluations have shown POC devices to have an acceptable level of precision. They permit INR results to be determined immediately, allowing for more rapid medication adjustments.
POC devices can be used in a variety of settings including physician offices, ACCs, long-term care facilities, pharmacies, or by the patients themselves through self-testing (PST) or self-management (PSM) techniques. With PST, patients measure their INR values and then contact their physician for instructions on dose adjustment, whereas with PSM, patients adjust the medication themselves based on pre-set algorithms. These models are not suitable for all patients and require the identification and education of suitable candidates.
Potential advantages of POC devices include improved convenience to patients, better treatment compliance and satisfaction, more frequent monitoring and fewer thromboembolic and hemorrhagic complications. Potential disadvantages of the device include the tendency to underestimate high INR values and overestimate low INR values, low thromboplastin sensitivity, inability to calculate a mean normal PT, and errors in INR determination in patients with antiphospholipid antibodies with certain instruments. Although treatment satisfaction and quality of life (QoL) may improve with POC INR monitoring, some patients may experience increased anxiety or preoccupation with their disease with these strategies.
Evidence-Based Analysis Methods
Research Questions
1. Effectiveness
Does POC INR monitoring improve clinical outcomes in various settings compared to standard laboratory-based testing?
Does POC INR monitoring impact patient satisfaction, QoL, compliance, acceptability, convenience compared to standard laboratory-based INR determination?
Settings include primary care settings with use of POC INR devices by general practitioners or nurses, ACCs, pharmacies, long-term care homes, and use by the patient either for PST or PSM.
2. Cost-effectiveness
What is the cost-effectiveness of POC INR monitoring devices in various settings compared to standard laboratory-based INR determination?
Inclusion Criteria
English-language RCTs, systematic reviews, and meta-analyses
Publication dates: 1996 to November 25, 2008
Population: patients on OAT
Intervention: anticoagulation monitoring by POC INR device in any setting including anticoagulation clinic, primary care (general practitioner or nurse), pharmacy, long-term care facility, PST, PSM or any other POC INR strategy
Minimum sample size: 50 patients Minimum follow-up period: 3 months
Comparator: usual care defined as venipuncture blood draw for an INR laboratory test and management provided by an ACC or individual practitioner
Outcomes: Hemorrhagic events, thromboembolic events, all-cause mortality, anticoagulation control as assessed by proportion of time or values in the therapeutic range, patient reported outcomes including satisfaction, QoL, compliance, acceptability, convenience
Exclusion criteria
Non-RCTs, before-after studies, quasi-experimental studies, observational studies, case reports, case series, editorials, letters, non-systematic reviews, conference proceedings, abstracts, non-English articles, duplicate publications
Studies where POC INR devices were compared to laboratory testing to assess test accuracy
Studies where the POC INR results were not used to guide patient management
Method of Review
A search of electronic databases (OVID MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, EMBASE, The Cochrane Library, and the International Agency for Health Technology Assessment [INAHTA] database) was undertaken to identify evidence published from January 1, 1998 to November 25, 2008. Studies meeting the inclusion criteria were selected from the search results. Reference lists of selected articles were also checked for relevant studies.
Summary of Findings
Five existing reviews and 22 articles describing 17 unique RCTs met the inclusion criteria. Three RCTs examined POC INR monitoring devices with PST strategies, 11 RCTs examined PSM strategies, one RCT included both PST and PSM strategies and two RCTs examined the use of POC INR monitoring devices by health care professionals.
Anticoagulation Control
Anticoagulation control is measured by the percentage of time INR is within the therapeutic range or by the percentage of INR values in the therapeutic range. Due to the differing methodologies and reporting structures used, it was deemed inappropriate to combine the data and estimate whether the difference between groups would be significant. Instead, the results of individual studies were weighted by the number of person-years of observation and then pooled to calculate a summary measure.
Across most studies, patients in the intervention groups tended to have a higher percentage of time and values in the therapeutic target range in comparison to control patients. When the percentage of time in the therapeutic range was pooled across studies and weighted by the number of person-years of observation, the difference between the intervention and control groups was 4.2% for PSM, 7.2% for PST and 6.1% for POC use by health care practitioners. Overall, intervention patients were in the target range 69% of the time and control patients were in the therapeutic target range 64% of the time leading to an overall difference between groups of roughly 5%.
Major Complications and Deaths
There was no statistically significant difference in the number of major hemorrhagic events between patients managed with POC INR monitoring devices and patients managed with standard laboratory testing (OR =0.74; 95% CI: 0.52- 1.04). This difference was non-significant for all POC strategies (PSM, PST, health care practitioner).
Patients managed with POC INR monitoring devices had significantly fewer thromboembolic events than usual care patients (OR =0.52; 95% CI: 0.37 - 0.74). When divided by POC strategy, PSM resulted in significantly fewer thromboembolic events than usual care (OR =0.46.; 95% CI: 0.29 - 0.72). The observed difference in thromboembolic events for PSM remained significant when the analysis was limited to major thromboembolic events (OR =0.40; 95% CI: 0.17 - 0.93), but was non-significant when the analysis was limited to minor thromboembolic events (OR =0.73; 95% CI: 0.08 - 7.01). PST and GP/Nurse strategies did not result in significant differences in thromboembolic events, however there were only a limited number of studies examining these interventions.
No statistically significant difference was observed in the number of deaths between POC intervention and usual care control groups (OR =0.67; 95% CI: 0.41 - 1.10). This difference was non-significant for all POC strategies. Only one study reported on survival with 10-year survival rate of 76.1% in the usual care control group compared to 84.5% in the PSM group (P=0.05).
Summary Results of Meta-Analyses of Major Complications and Deaths in POC INR Monitoring Studies
Patient Satisfaction and Quality of Life
Quality of life measures were reported in eight studies comparing POC INR monitoring to standard laboratory testing using a variety of measurement tools. It was thus not possible to calculate a quantitative summary measure. The majority of studies reported favourable impacts of POC INR monitoring on QoL and found better treatment satisfaction with POC monitoring. Results from a pre-analysis patient and caregiver focus group conducted in Ontario also indicated improved patient QoL with POC monitoring.
Quality of the Evidence
Studies varied with regard to patient eligibility, baseline patient characteristics, follow-up duration, and withdrawal rates. Differential drop-out rates were observed such that the POC intervention groups tended to have a larger number of patients who withdrew. There was a lack of consistency in the definitions and reporting for OAT control and definitions of adverse events. In most studies, the intervention group received more education on the use of warfarin and performed more frequent INR testing, which may have overestimated the effect of the POC intervention. Patient selection and eligibility criteria were not always fully described and it is likely that the majority of the PST/PSM trials included a highly motivated patient population. Lastly, a large number of trials were also sponsored by industry.
Despite the observed heterogeneity among studies, there was a general consensus in findings that POC INR monitoring devices have beneficial impacts on the risk of thromboembolic events, anticoagulation control and patient satisfaction and QoL (ES Table 2).
GRADE Quality of the Evidence on POC INR Monitoring Studies
CI refers to confidence interval; Interv, intervention; OR, odds ratio; RCT, randomized controlled trial.
Economic Analysis
Using a 5-year Markov model, the health and economic outcomes associated with four different anticoagulation management approaches were evaluated:
Standard care: consisting of a laboratory test with a venipuncture blood draw for an INR;
Healthcare staff testing: consisting of a test with a POC INR device in a medical clinic comprised of healthcare staff such as pharmacists, nurses, and physicians following protocol to manage OAT;
PST: patient self-testing using a POC INR device and phoning in results to an ACC or family physician; and
PSM: patient self-managing using a POC INR device and self-adjustment of OAT according to a standardized protocol. Patients may also phone in to a medical office for guidance.
The primary analytic perspective was that of the MOHLTC. Only direct medical costs were considered and the time horizon of the model was five years - the serviceable life of a POC device.
From the results of the economic analysis, it was found that POC strategies are cost-effective compared to traditional INR laboratory testing. In particular, the healthcare staff testing strategy can derive potential cost savings from the use of one device for multiple patients. The PSM strategy, however, seems to be the most cost-effective method i.e. patients are more inclined to adjust their INRs more readily (as opposed to allowing INRs to fall out of range).
Considerations for Ontario Health System
Although the use of POC devices continues to diffuse throughout Ontario, not all OAT patients are suitable or have the ability to practice PST/PSM. The use of POC is currently concentrated at the institutional setting, including hospitals, ACCs, long-term care facilities, physician offices and pharmacies, and is much less commonly used at the patient level. It is, however, estimated that 24% of OAT patients (representing approximately 32,000 patients in Ontario), would be suitable candidates for PST/PSM strategies and willing to use a POC device.
There are several barriers to the use and implementation of POC INR monitoring devices, including factors such as lack of physician familiarity with the devices, resistance to changing established laboratory-based methods, lack of an approach for identifying suitable patients and inadequate resources for effective patient education and training. Issues of cost and insufficient reimbursement strategies may also hinder implementation and effective quality assurance programs would need to be developed to ensure that INR measurements are accurate and precise.
For a select group of patients who are highly motivated and trained, PSM resulted in significantly fewer thromboembolic events compared to conventional laboratory-based INR testing. No significant differences were observed for major hemorrhages or all-cause mortality. PST and GP/Nurse use of POC strategies are just as effective as conventional laboratory-based INR testing for thromboembolic events, major hemorrhages, and all-cause mortality. POC strategies may also result in better OAT control as measured by the proportion of time INR is in the therapeutic range and there appears to be beneficial impacts on patient satisfaction and QoL. The use of POC devices should factor in patient suitability, patient education and training, health system constraints, and affordability.
anticoagulants, International Normalized Ratio, point-of-care, self-monitoring, warfarin.
PMCID: PMC3377545  PMID: 23074516
15.  Comparison of Treatment Effect Estimates for Pharmacological Randomized Controlled Trials Enrolling Older Adults Only and Those including Adults: A Meta-Epidemiological Study 
PLoS ONE  2013;8(5):e63677.
Older adults are underrepresented in clinical research. To assess therapeutic efficacy in older patients, some randomized controlled trials (RCTs) include older adults only.
To compare treatment effects between RCTs including older adults only (elderly RCTs) and RCTs including all adults (adult RCTs) by a meta-epidemiological approach.
All systematic reviews published in the Cochrane Library (Issue 4, 2011) were screened. Eligible studies were meta-analyses of binary outcomes of pharmacologic treatment including at least one elderly RCT and at least one adult RCT. For each meta-analysis, we compared summary odds ratios for elderly RCTs and adult RCTs by calculating a ratio of odds ratios (ROR). A summary ROR was estimated across all meta-analyses.
We selected 55 meta-analyses including 524 RCTs (17% elderly RCTs). The treatment effects differed beyond that expected by chance for 7 (13%) meta-analyses, showing more favourable treatment effects in elderly RCTs in 5 cases and in adult RCTs in 2 cases. The summary ROR was 0.91 (95% CI, 0.77–1.08, p = 0.28), with substantial heterogeneity (I2 = 51% and τ2 = 0.14). Sensitivity and subgroup analyses by type-of-age RCT (elderly RCTs vs RCTs excluding older adults and vs RCTs of mixed-age adults), type of outcome (mortality or other) and type of comparator (placebo or active drug) yielded similar results.
The efficacy of pharmacologic treatments did not significantly differ, on average, between RCTs including older adults only and RCTs of all adults. However, clinically important discrepancies may occur and should be considered when generalizing evidence from all adults to older adults.
PMCID: PMC3665786  PMID: 23723992
16.  Screening Mammography for Women Aged 40 to 49 Years at Average Risk for Breast Cancer 
Executive Summary
The aim of this review was to determine the effectiveness of screening mammography in women aged 40 to 49 years at average risk for breast cancer.
Clinical Need
The effectiveness of screening mammography in women aged over 50 years has been established, yet the issue of screening in women aged 40 to 49 years is still unsettled. The Canadian Task Force of Preventive Services, which sets guidelines for screening mammography for all provinces, supports neither the inclusion nor the exclusion of this screening procedure for 40- to 49-year-old women from the periodic health examination. In addition to this, 2 separate reviews, one conducted in Quebec in 2005 and the other in Alberta in 2000, each concluded that there is an absence of convincing evidence on the effectiveness of screening mammography for women in this age group who are at average risk for breast cancer.
In the United States, there is disagreement among organizations on whether population-based mammography should begin at the age of 40 or 50 years. The National Institutes of Health, the American Association for Cancer Research, and the American Academy of Family Physicians recommend against screening women in their 40s, whereas the United States Preventive Services Task Force, the National Cancer Institute, the American Cancer Society, the American College of Radiology, and the American College of Obstetricians and Gynecologists recommend screening mammograms for women aged 40 to 49 years. Furthermore, in comparing screening guidelines between Canada and the United States, it is also important to recognize that “standard care” within a socialized medical system such as Canada’s differs from that of the United States. The National Breast Screening Study (NBSS-1), a randomized screening trial conducted in multiple centres across Canada, has shown there is no benefit in mortality from breast cancer from annual mammograms in women randomized between the ages of 40 and 49, relative to standard care (i.e. physical exam and teaching of breast-self examination on entry to the study, with usual community care thereafter).
At present, organized screening programs in Canada systematically screen women starting at 50 years of age, although with a physician’s referral, a screening mammogram is an insured service in Ontario for women under 50 years of age.
International estimates of the epidemiology of breast cancer show that the incidence of breast cancer is increasing for all ages combined, whereas mortality is decreasing, though at a slower rate. These decreasing mortality rates may be attributed to screening and advances in breast cancer therapy over time. Decreases in mortality attributable to screening may be a result of the earlier detection and treatment of invasive cancers, in addition to the increased detection of ductal carcinoma in situ (DCIS), of which certain subpathologies are less lethal. Evidence from the SEER cancer registry in the United States indicates that the age-adjusted incidence of DCIS has increased almost 10-fold over a 20-year period (from 2.7 to 25 per 100,000).
The incidence of breast cancer is lower in women aged 40 to 49 years than in women aged 50 to 69 years (about 140 per 100,000 versus 500 per 100,000 women, respectively), as is the sensitivity (about 75% versus 85% for women aged under and over 50, respectively) and specificity of mammography (about 80% versus 90% for women aged under and over 50, respectively). The increased density of breast tissue in younger women is mainly responsible for the lower accuracy of this procedure in this age group. In addition, as the proportion of breast cancers that occur before the age of 50 are more likely to be associated with genetic predisposition as compared with those diagnosed in women after the age of 50, mammography may not be an optimal screening method for younger women.
Treatment options vary with the stage of disease (based on tumor size, involvement of surrounding tissue, and number of affected axillary lymph nodes) and its pathology, and may include a combination of surgery, chemotherapy, and/or radiotherapy.
Surgery is the first-line intervention for biopsy confirmed tumours. The subsequent use of radiation, chemotherapy, or hormonal treatments is dependent on the histopathologic characteristics of the tumor and the type of surgery. There is controversy regarding the optimal treatment of DCIS, which is noninvasive.
With such controversy as to the effectiveness of mammography and the potential risk associated with women being overtreated or actual cancers being missed, and the increased risk of breast cancer associated with exposure to annual mammograms over a 10-year period, the Ontario Health Technology Advisory Committee requested this review of screening mammography in women aged 40 to 49 years at average risk for breast cancer. This review is the first of 2 parts and concentrates on the effectiveness of screening mammography (i.e., film mammography, FM) for women at average risk aged 40 to 49 years. The second part will be an evaluation of screening by either magnetic resonance imaging or digital mammography, with the objective of determining the optimal screening modality in these younger women.
Review Strategy
The following questions were asked:
Does screening mammography for women aged 40 to 49 years who are at average risk for breast cancer reduce breast cancer mortality?
What is the sensitivity and specificity of mammography for this age group?
What are the risks associated with annual screening from ages 40 to 49?
What are the risks associated with false positive and false negative mammography results?
What are the economic considerations if evidence for effectiveness is established?
The Medical Advisory Secretariat followed its standard procedures and searched these electronic databases: Ovid MEDLINE, EMBASE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews and the International Network of Agencies for Health Technology Assessment.
Keywords used in the search were breast cancer, breast neoplasms, mass screening, and mammography.
In total, the search yielded 6,359 articles specific to breast cancer screening and mammography. This did not include reports on diagnostic mammograms. The search was further restricted to English-language randomized controlled trials (RCTs), systematic reviews, and meta-analyses published between 1995 and 2005. Excluded were case reports, comments, editorials, and letters, which narrowed the results to 516 articles and previous health technology policy assessments.
These were examined against the criteria outlined below. This resulted in the inclusion of 5 health technology assessments, the Canadian Preventive Services Task Force report, the United States Preventive Services Task Force report, 1 Cochrane review, and 8 RCTs.
Inclusion Criteria
English-language articles, and English and French-language health technology policy assessments, conducted by other organizations, from 1995 to 2005
Articles specific to RCTs of screening mammography of women at average risk for breast cancer that included results for women randomized to studies between the ages of 40 and 49 years
Studies in which women were randomized to screening with or without mammography, although women may have had clinical breast examinations and/or may have been conducting breast self-examination.
UK Age Trial results published in December 2006.
Exclusion Criteria
Observational studies, including those nested within RCTs
RCTs that do not include results on women between the ages of 40 and 49 at randomization
Studies in which mammography was compared with other radiologic screening modalities, for example, digital mammography, magnetic resonance imaging or ultrasound.
Studies in which women randomized had a personal history of breast cancer.
Film mammography
Within RCTs, the comparison group would have been women randomized to not undergo screening mammography, although they may have had clinical breast examinations and/or have been conducting breast self-examination.
Outcomes of Interest
Breast cancer mortality
Summary of Findings
There is Level 1 Canadian evidence that screening women between the ages of 40 and 49 years who are at average risk for breast cancer is not effective, and that the absence of a benefit is sustained over a maximum follow-up period of 16 years.
All remaining studies that reported on women aged under 50 years were based on subset analyses. They provide additional evidence that, when all these RCTs are taken into account, there is no significant reduction in breast cancer mortality associated with screening mammography in women aged 40 to 49 years.
There is Level 1 evidence that screening mammography in women aged 40 to 49 years at average risk for breast cancer is not effective in reducing mortality.
Moreover, risks associated with exposure to mammographic radiation, the increased risk of missed cancers due to lower mammographic sensitivity, and the psychological impact of false positives, are not inconsequential.
The UK Age Trial results published in December 2006 did not change these conclusions.
PMCID: PMC3377515  PMID: 23074501
17.  Effectiveness of smoking cessation therapies: a systematic review and meta-analysis 
BMC Public Health  2006;6:300.
Smoking remains the leading preventable cause of premature deaths. Several pharmacological interventions now exist to aid smokers in cessation. These include Nicotine Replacement Therapy [NRT], bupropion, and varenicline. We aimed to assess their relative efficacy in smoking cessation by conducting a systematic review and meta-analysis.
We searched 10 electronic medical databases (inception to Sept. 2006) and bibliographies of published reviews. We selected randomized controlled trials [RCTs] evaluating interventions for smoking cessation at 1 year, through chemical confirmation. Our primary endpoint was smoking cessation at 1 year. Secondary endpoints included short-term smoking cessation (~3 months) and adverse events. We conducted random-effects meta-analysis and meta-regression. We compared treatment effects across interventions using head-to-head trials and when these did not exist, we calculated indirect comparisons.
We identified 70 trials of NRT versus control at 1 year, Odds Ratio [OR] 1.71, 95% Confidence Interval [CI], 1.55–1.88, P =< 0.0001). This was consistent when examining all placebo-controlled trials (49 RCTs, OR 1.78, 95% CI, 1.60–1.99), NRT gum (OR 1.60, 95% CI, 1.37–1.86) or patch (OR 1.63, 95% CI, 1.41–1.89). NRT also reduced smoking at 3 months (OR 1.98, 95% CI, 1.77–2.21). Bupropion trials were superior to controls at 1 year (12 RCTs, OR1.56, 95% CI, 1.10–2.21, P = 0.01) and at 3 months (OR 2.13, 95% CI, 1.72–2.64). Two RCTs evaluated the superiority of bupropion versus NRT at 1 year (OR 1.14, 95% CI, 0.20–6.42).
Varenicline was superior to placebo at 1 year (4 RCTs, OR 2.96, 95% CI, 2.12–4.12, P =< 0.0001) and also at approximately 3 months (OR 3.75, 95% CI, 2.65–5.30). Three RCTs evaluated the effectiveness of varenicline versus bupropion at 1 year (OR 1.58, 95% CI, 1.22–2.05) and at approximately 3 months (OR 1.61, 95% CI, 1.16–2.21). Using indirect comparisons, varenicline was superior to NRT when compared to placebo controls (OR 1.66, 95% CI 1.17–2.36, P = 0.004) or to all controls at 1 year (OR 1.73, 95% CI 1.22–2.45, P = 0.001). This was also the case for 3-month data. Adverse events were not systematically different across studies.
NRT, bupropion and varenicline all provide therapeutic effects in assisting with smoking cessation. Direct and indirect comparisons identify a hierarchy of effectiveness.
PMCID: PMC1764891  PMID: 17156479
18.  Noninvasive Positive Pressure Ventilation for Chronic Respiratory Failure Patients With Stable Chronic Obstructive Pulmonary Disease (COPD) 
Executive Summary
In July 2010, the Medical Advisory Secretariat (MAS) began work on a Chronic Obstructive Pulmonary Disease (COPD) evidentiary framework, an evidence-based review of the literature surrounding treatment strategies for patients with COPD. This project emerged from a request by the Health System Strategy Division of the Ministry of Health and Long-Term Care that MAS provide them with an evidentiary platform on the effectiveness and cost-effectiveness of COPD interventions.
After an initial review of health technology assessments and systematic reviews of COPD literature, and consultation with experts, MAS identified the following topics for analysis: vaccinations (influenza and pneumococcal), smoking cessation, multidisciplinary care, pulmonary rehabilitation, long-term oxygen therapy, noninvasive positive pressure ventilation for acute and chronic respiratory failure, hospital-at-home for acute exacerbations of COPD, and telehealth (including telemonitoring and telephone support). Evidence-based analyses were prepared for each of these topics. For each technology, an economic analysis was also completed where appropriate. In addition, a review of the qualitative literature on patient, caregiver, and provider perspectives on living and dying with COPD was conducted, as were reviews of the qualitative literature on each of the technologies included in these analyses.
The Chronic Obstructive Pulmonary Disease Mega-Analysis series is made up of the following reports, which can be publicly accessed at the MAS website at:
Chronic Obstructive Pulmonary Disease (COPD) Evidentiary Framework
Influenza and Pneumococcal Vaccinations for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Smoking Cessation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Community-Based Multidisciplinary Care for Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Pulmonary Rehabilitation for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Long-term Oxygen Therapy for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Acute Respiratory Failure Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Noninvasive Positive Pressure Ventilation for Chronic Respiratory Failure Patients With Stable Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Hospital-at-Home Programs for Patients With Acute Exacerbations of Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Home Telehealth for Patients With Chronic Obstructive Pulmonary Disease (COPD): An Evidence-Based Analysis
Cost-Effectiveness of Interventions for Chronic Obstructive Pulmonary Disease Using an Ontario Policy Model
Experiences of Living and Dying With COPD: A Systematic Review and Synthesis of the Qualitative Empirical Literature
For more information on the qualitative review, please contact Mita Giacomini at:
For more information on the economic analysis, please visit the PATH website:
The Toronto Health Economics and Technology Assessment (THETA) collaborative has produced an associated report on patient preference for mechanical ventilation. For more information, please visit the THETA website:
The objective of this health technology assessment was to determine the effectiveness and cost-effectiveness of noninvasive ventilation for stable chronic obstructive pulmonary disease (COPD).
Clinical Need: Condition and Target Population
Noninvasive ventilation is used for COPD patients with chronic respiratory failure. Chronic respiratory failure in COPD patients may be due to the inability of the pulmonary system to coordinate ventilation, leading to adverse arterial levels of oxygen and carbon dioxide. Noninvasive ventilation in stable COPD patients has the potential to improve quality of life, prolong survival, and improve gas exchange and sleep quality in patients who are symptomatic after optimal therapy, have hypercapnia or nocturnal hypoventilation and mild hypercapnia, and are frequently hospitalized.
Noninvasive positive pressure ventilation (NPPV) is any form of positive ventilatory support without the use of an endotracheal tube. For stable COPD, the standard of care when using noninvasive ventilation is bilevel positive airway pressure (BiPAP). Bilevel positive airway pressure involves both inspiratory and expiratory pressure, high during inspiration and lower during expiration. It acts as a pressure support to accentuate a patient’s inspiratory efforts. The gradient between pressures maintains alveolar ventilation and helps to reduce carbon dioxide levels. Outpatients typically use BiPAP at night. Additional advantages of using BiPAP include resting of respiratory muscles, decreased work of breathing, and control of obstructive hypopnea.
Research Question
What is the effectiveness and cost-effectiveness of noninvasive ventilation, compared with no ventilation while receiving usual care, for stable COPD patients?
Research Methods
Literature Search
Search Strategy
A literature search was performed on December 3, 2010, using OVID MEDLINE, OVID MEDLINE In-Process and Other Non-Indexed Citations, OVID EMBASE, EBSCO Cumulative Index to Nursing & Allied Health Literature (CINAHL), the Wiley Cochrane Library, and the Centre for Reviews and Dissemination database for studies published from January 1, 2004 to December 3, 2010. Abstracts were reviewed by a single reviewer and, for those studies meeting the eligibility criteria, full-text articles were obtained. Reference lists were also examined for any additional relevant studies not identified through the search. When the reviewer was unsure of the eligibility of articles, a second clinical epidemiologist and then a group of epidemiologists reviewed these until consensus was reached.
Inclusion Criteria
full-text English language articles,
studies published between January 1, 2004 and December 3, 2010,
journal articles that report on the effectiveness or cost-effectiveness of noninvasive ventilation,
clearly described study design and methods, and
health technology assessments, systematic reviews, meta-analyses, randomized controlled trials (RCTs).
Exclusion Criteria
non-English papers
animal or in vitro studies
case reports, case series, or case-case studies
cross-over RCTs
studies on noninvasive negative pressure ventilation (e.g., iron lung)
studies that combine ventilation therapy with other regimens (e.g., daytime NPPV plus exercise or pulmonary rehabilitation)
studies on heliox with NPPV
studies on pulmonary rehabilitation with NPPV
Outcomes of Interest
length of stay in hospital
forced expiratory volume
arterial partial pressure of oxygen
arterial partial pressure of carbon dioxide
exercise tolerance
health-related quality of life
Note: arterial pressure of oxygen and carbon dioxide are surrogate outcomes.
Statistical Methods
A meta-analysis and an analysis of individual studies were performed using Review Manager Version 5. For continuous data, a mean difference was calculated, and for dichotomous data, a relative risk ratio was calculated for RCTs. For continuous variables with mean baseline and mean follow-up data, a change value was calculated as the difference between the 2 mean values.
Quality of Evidence
The quality of each included study was assessed taking into consideration allocation concealment, randomization, blinding, power/sample size, withdrawals/dropouts, and intention-to-treat analyses.
The quality of the body of evidence was assessed as high, moderate, low, or very low according to the GRADE Working Group criteria. The following definitions of quality were used in grading the quality of the evidence:
Summary of Findings
The following conclusions refer to stable, severe COPD patients receiving usual care.
Short-Term Studies
Based on low quality of evidence, there is a beneficial effect of NPPV compared with no ventilation on oxygen gas exchange, carbon dioxide gas exchange, and exercise tolerance measured using the 6 Minute Walking Test.
Based on very low quality of evidence, there is no effect of NPPV therapy on lung function measured as forced expiratory volume in 1 second (Type II error not excluded).
Long-Term Studies
Based on moderate quality of evidence, there is no effect of NPPV therapy for the outcomes of mortality, lung function measured as forced expiratory volume in 1 second, and exercise tolerance measured using the 6 Minute Walking Test.
Based on low quality of evidence, there is no effect of NPPV therapy for the outcomes of oxygen gas exchange and carbon dioxide gas exchange (Type II error not excluded).
Qualitative Assessment
Based on low quality of evidence, there is a beneficial effect of NPPV compared with no ventilation for dyspnea based on reduced Borg score or Medical Research Council dyspnea score.
Based on moderate quality of evidence, there is no effect of NPPV therapy for hospitalizations.
Health-related quality of life could not be evaluated.
PMCID: PMC3384378  PMID: 23074437
19.  Inadequate Dissemination of Phase I Trials: A Retrospective Cohort Study 
PLoS Medicine  2009;6(2):e1000034.
Drug development is ideally a logical sequence in which information from small early studies (Phase I) is subsequently used to inform and plan larger, more definitive studies (Phases II–IV). Phase I trials are unique because they generally provide the first evaluation of new drugs in humans. The conduct and dissemination of Phase I trials have not previously been empirically evaluated. Our objective was to describe the initiation, completion, and publication of Phase I trials in comparison with Phase II–IV trials.
Methods and Findings
We reviewed a cohort of all protocols approved by a sample of ethics committees in France from January 1, 1994 to December 31, 1994. The comparison of 140 Phase I trials with 304 Phase II–IV trials, showed that Phase I studies were more likely to be initiated (133/140 [95%] versus 269/304 [88%]), more likely to be completed (127/133 [95%] versus 218/269 [81%]), and more likely to produce confirmatory results (71/83 [86%] versus 125/175 [71%]) than Phase II–IV trials. Publication was less frequent for Phase I studies (21/127 [17%] versus 93/218 [43%]), even if only accounting for studies providing confirmatory results (18/71 [25%] versus 79/125 [63%]).
The initiation, completion, and publications of Phase I trials are different from those of other studies. Moreover, the results of these trials should be published in order to ensure the integrity of the overall body of scientific knowledge, and ultimately the safety of future trial participants and patients.
François Chapuis and colleagues examine a cohort of clinical trial protocols approved by French ethics committees, and show that Phase I trials are less frequently published than other types of trials.
Editors' Summary
Before a new drug is used to treat patients, its benefits and harms have to be carefully investigated in clinical trials—studies that investigate the drug's effects on people. Because giving any new drug to people is potentially dangerous, drugs are first tested in a short “Phase I” trial in which a few people (usually healthy volunteers) are given doses of the drug likely to have a therapeutic effect. A Phase I trial evaluates the safety and tolerability of the drug and investigates how the human body handles the drug. It may also provide some information about the drug's efficacy that can guide the design of later trials. The next stage of clinical drug development is a Phase II trial in which the therapeutic efficacy of the drug is investigated by giving more patients and volunteers different doses of the drug. Finally, several large Phase III trials are undertaken to confirm the evidence collected in the Phase II trial about the drug's efficacy and safety. If the Phase III trials are successful, the drug will receive official marketing approval. In some cases, this approval requires Phase IV (postapproval) trials to be done to optimize the drug's use in clinical practice.
Why Was This Study Done?
In an ideal world, the results of all clinical trials on new drugs would be published in medical journals so that doctors and patients could make fully informed decisions about the treatments available to them. Unfortunately, this is not an ideal world and, for example, it is well known that the results of Phase III trials in which a new drug outperforms a standard treatment are more likely to be published than those in which the new drug performs badly or has unwanted side effects (an example of “publication bias”). But what about the results of Phase I trials? These need to be widely disseminated so that researchers can avoid unknowingly exposing people to potentially dangerous new drugs after similar drugs have caused adverse side effects. However, drug companies are often reluctant to disclose information on early phase trials. In this study, the researchers ask whether the dissemination of the results of Phase I trials is adequate.
What Did the Researchers Do and Find?
The researchers identified 667 drug trial protocols approved in 1994 by 25 French research ethics committees (independent panels of experts that ensure that the rights, safety, and well-being of trial participants are protected). In 2001, questionnaires were mailed to each trial's principal investigator asking whether the trial had been started and completed and whether its results had been published in a medical journal or otherwise disseminated (for example, by presentation at a scientific meeting). 140 questionnaires for Phase I trials and 304 for Phase II–IV trials were returned and analyzed by the investigators. They found that Phase I trials were more likely to have been started and to have been completed than Phase II–IV trials. The results of 86% of the Phase I studies matched the researchers' expectations, but the study hypothesis was confirmed in only 71% of the Phase II–IV trials. Finally, the results of 17% of the Phase I studies were published in scientific journals compared to 43% of the Phase II–IV studies. About half of the Phase I study results were not disseminated in any form.
What Do These Findings Mean?
These findings suggest that the fate of Phase I trials is different from that of other clinical trials and that there is inadequate dissemination of the results of these early trials. These findings may not be generalizable to other countries and may be affected by the poor questionnaire response rate. Nevertheless, they suggest that steps need to be taken to ensure that the results of Phase I studies are more widely disseminated. Recent calls by the World Health Organization and other bodies for mandatory preregistration in trial registries of all Phase I trials as well as all Phase II–IV trials should improve the situation by providing basic information about Phase I trials whose results are not published in full elsewhere.
Additional Information.
Please access these Web sites via the online version of this summary at
Two recent research articles published in PLoS Medicine—by Ida Sim and colleagues (PLoS Med e191) and by Lisa Bero and colleagues (PLoS Med e217)—investigate publication bias in Phase III trials
The Web site provides information about the US National Institutes of Health clinical trial registry, background information about clinical trials, and a fact sheet detailing the requirements of the US Food and Drug Administration (the body that approves drugs in the USA) Amendments Act 2007 for trial registration
The World Health Organization's International Clinical Trials Registry Platform is working toward setting international norms and standards for the reporting of clinical trials (in several languages)
PMCID: PMC2642878  PMID: 19226185
20.  Meta-analyses of Adverse Effects Data Derived from Randomised Controlled Trials as Compared to Observational Studies: Methodological Overview 
PLoS Medicine  2011;8(5):e1001026.
Su Golder and colleagues carry out an overview of meta-analyses to assess whether estimates of the risk of harm outcomes differ between randomized trials and observational studies. They find that, on average, there is no difference in the estimates of risk between overviews of observational studies and overviews of randomized trials.
There is considerable debate as to the relative merits of using randomised controlled trial (RCT) data as opposed to observational data in systematic reviews of adverse effects. This meta-analysis of meta-analyses aimed to assess the level of agreement or disagreement in the estimates of harm derived from meta-analysis of RCTs as compared to meta-analysis of observational studies.
Methods and Findings
Searches were carried out in ten databases in addition to reference checking, contacting experts, citation searches, and hand-searching key journals, conference proceedings, and Web sites. Studies were included where a pooled relative measure of an adverse effect (odds ratio or risk ratio) from RCTs could be directly compared, using the ratio of odds ratios, with the pooled estimate for the same adverse effect arising from observational studies. Nineteen studies, yielding 58 meta-analyses, were identified for inclusion. The pooled ratio of odds ratios of RCTs compared to observational studies was estimated to be 1.03 (95% confidence interval 0.93–1.15). There was less discrepancy with larger studies. The symmetric funnel plot suggests that there is no consistent difference between risk estimates from meta-analysis of RCT data and those from meta-analysis of observational studies. In almost all instances, the estimates of harm from meta-analyses of the different study designs had 95% confidence intervals that overlapped (54/58, 93%). In terms of statistical significance, in nearly two-thirds (37/58, 64%), the results agreed (both studies showing a significant increase or significant decrease or both showing no significant difference). In only one meta-analysis about one adverse effect was there opposing statistical significance.
Empirical evidence from this overview indicates that there is no difference on average in the risk estimate of adverse effects of an intervention derived from meta-analyses of RCTs and meta-analyses of observational studies. This suggests that systematic reviews of adverse effects should not be restricted to specific study types.
Please see later in the article for the Editors' Summary
Editors' Summary
Whenever patients consult a doctor, they expect the treatments they receive to be effective and to have minimal adverse effects (side effects). To ensure that this is the case, all treatments now undergo exhaustive clinical research—carefully designed investigations that test new treatments and therapies in people. Clinical investigations fall into two main groups—randomized controlled trials (RCTs) and observational, or non-randomized, studies. In RCTs, groups of patients with a specific disease or condition are randomly assigned to receive the new treatment or a control treatment, and the outcomes (for example, improvements in health and the occurrence of specific adverse effects) of the two groups of patients are compared. Because the patients are randomly chosen, differences in outcomes between the two groups are likely to be treatment-related. In observational studies, patients who are receiving a specific treatment are enrolled and outcomes in this group are compared to those in a similar group of untreated patients. Because the patient groups are not randomly chosen, differences in outcomes between cases and controls may be the result of a hidden shared characteristic among the cases rather than treatment-related (so-called confounding variables).
Why Was This Study Done?
Although data from individual trials and studies are valuable, much more information about a potential new treatment can be obtained by systematically reviewing all the evidence and then doing a meta-analysis (so-called evidence-based medicine). A systematic review uses predefined criteria to identify all the research on a treatment; meta-analysis is a statistical method for combining the results of several studies to yield “pooled estimates” of the treatment effect (the efficacy of a treatment) and the risk of harm. Treatment effect estimates can differ between RCTs and observational studies, but what about adverse effect estimates? Can different study designs provide a consistent picture of the risk of harm, or are the results from different study designs so disparate that it would be meaningless to combine them in a single review? In this methodological overview, which comprises a systematic review and meta-analyses, the researchers assess the level of agreement in the estimates of harm derived from meta-analysis of RCTs with estimates derived from meta-analysis of observational studies.
What Did the Researchers Do and Find?
The researchers searched literature databases and reference lists, consulted experts, and hand-searched various other sources for studies in which the pooled estimate of an adverse effect from RCTs could be directly compared to the pooled estimate for the same adverse effect from observational studies. They identified 19 studies that together covered 58 separate adverse effects. In almost all instances, the estimates of harm obtained from meta-analyses of RCTs and observational studies had overlapping 95% confidence intervals. That is, in statistical terms, the estimates of harm were similar. Moreover, in nearly two-thirds of cases, there was agreement between RCTs and observational studies about whether a treatment caused a significant increase in adverse effects, a significant decrease, or no significant change (a significant change is one unlikely to have occurred by chance). Finally, the researchers used meta-analysis to calculate that the pooled ratio of the odds ratios (a statistical measurement of risk) of RCTs compared to observational studies was 1.03. This figure suggests that there was no consistent difference between risk estimates obtained from meta-analysis of RCT data and those obtained from meta-analysis of observational study data.
What Do These Findings Mean?
The findings of this methodological overview suggest that there is no difference on average in the risk estimate of an intervention's adverse effects obtained from meta-analyses of RCTs and from meta-analyses of observational studies. Although limited by some aspects of its design, this overview has several important implications for the conduct of systematic reviews of adverse effects. In particular, it suggests that, rather than limiting systematic reviews to certain study designs, it might be better to evaluate a broad range of studies. In this way, it might be possible to build a more complete, more generalizable picture of potential harms associated with an intervention, without any loss of validity, than by evaluating a single type of study. Such a picture, in combination with estimates of treatment effects also obtained from systematic reviews and meta-analyses, would help clinicians decide the best treatment for their patients.
Additional Information
Please access these Web sites via the online version of this summary at
The US National Institutes of Health provide information on clinical research; the UK National Health Service Choices Web site also has a page on clinical trials and medical research
The Cochrane Collaboration produces and disseminates systematic reviews of health-care interventions
Medline Plus provides links to further information about clinical trials (in English and Spanish)
PMCID: PMC3086872  PMID: 21559325
21.  Percutaneous Vertebroplasty for Treatment of Painful Osteoporotic Vertebral Compression Fractures 
Executive Summary
Objective of Analysis
The objective of this analysis is to examine the safety and effectiveness of percutaneous vertebroplasty for treatment of osteoporotic vertebral compression fractures (VCFs) compared with conservative treatment.
Clinical Need and Target Population
Osteoporosis and associated fractures are important health issues in ageing populations. Vertebral compression fracture secondary to osteoporosis is a cause of morbidity in older adults. VCFs can affect both genders, but are more common among elderly females and can occur as a result of a fall or a minor trauma. The fracture may occur spontaneously during a simple activity such as picking up an object or rising up from a chair. Pain originating from the fracture site frequently increases with weight bearing. It is most severe during the first few weeks and decreases with rest and inactivity.
Traditional treatment of painful VCFs includes bed rest, analgesic use, back bracing and muscle relaxants. The comorbidities associated with VCFs include deep venous thrombosis, acceleration of osteopenea, loss of height, respiratory problems and emotional problems due to chronic pain.
Percutaneous vertebroplasty is a minimally invasive surgical procedure that has gained popularity as a new treatment option in the care for these patients. The technique of vertebroplasty was initially developed in France to treat osteolytic metastasis, myeloma, and hemangioma. The indications were further expanded to painful osteoporotic VCFs and subsequently to treatment of asymptomatic VCFs.
The mechanism of pain relief, which occurs within minutes to hours after vertebroplasty, is still not known. Pain pathways in the surrounding tissue appear to be altered in response to mechanical, chemical, vascular, and thermal stimuli after the injection of the cement. It has been suggested that mechanisms other than mechanical stabilization of the fracture, such as thermal injury to the nerve endings, results in immediate pain relief.
Percutaneous Vertebroplasty
Percutaneous vertebroplasty is performed with the patient in prone position and under local or general anesthesia. The procedure involves fluoroscopic imaging to guide the injection of bone cement into the fractured vertebral body to support the fractured bone. After injection of the cement, the patient is placed in supine position for about 1 hour while the cement hardens.
Cement leakage is the most frequent complication of vertebroplasty. The leakages may remain asymptomatic or cause symptoms of nerve irritation through compression of nerve roots. There are several reports of pulmonary cement embolism (PCE) following vertebroplasty. In some cases, the PCE may remain asymptomatic. Symptomatic PCE can be recognized by their clinical signs and symptoms such as chest pain, dyspnea, tachypnea, cyanosis, coughing, hemoptysis, dizziness, and sweating.
Research Methods
Literature Search
A literature search was performed on Feb 9, 2010 using OVID MEDLINE, MEDLINE In-Process and Other Non-Indexed Citations, EMBASE, the Cumulative Index to Nursing & Allied Health Literature (CINAHL), the Cochrane Library, and the International Agency for Health Technology Assessment (INAHTA) for studies published from January 1, 2005 to February 9, 2010.
Studies were initially reviewed by titles and abstracts. For those studies meeting the eligibility criteria, full-text articles were obtained and reviewed. Reference lists were also examined for any additional relevant studies not identified through the search. Articles with an unknown eligibility were reviewed with a second clinical epidemiologist and then a group of epidemiologists until consensus was established. Data extraction was carried out by the author.
Inclusion Criteria
Study design: Randomized controlled trials (RCTs) comparing vertebroplasty with a control group or other interventions
Study population: Adult patients with osteoporotic vertebral fractures
Study sample size: Studies included 20 or more patients
English language full-reports
Published between Jan 1 2005 and Feb 9, 2010
(eligible studies identified through the Auto Alert function of the search were also included)
Exclusion Criteria
Non-randomized studies
Studies on conditions other than VCF (e.g. patients with multiple myeloma or metastatic tumors)
Studies focused on surgical techniques
Studies lacking outcome measures
Results of Evidence-Based Analysis
A systematic search yielded 168 citations. The titles and the abstracts of the citations were reviewed and full text of the identified citations was retrieved for further consideration. Upon review of the full publications and applying the inclusion and exclusion criteria, 5 RCTs were identified. Of these, two compared vertebroplasty with sham procedure, two compared vertebroplasty with conservative treatment, and one compared vertebroplasty with balloon kyphoplasty.
Randomized Controlled Trials
Recently, the results of two blinded randomized placebo-controlled trials of percutaneous vertebroplasty were reported. These trials, providing the highest quality of evidence available to date, do not support the use of vertebroplasty in patients with painful osteoporotic vertebral compression fractures. Based on the results of these trials, vertebroplasty offer no additional benefit over usual care and is not risk free.
In these trials the treatment allocation was blinded to the patients and outcome assessors. The control group received a sham procedure simulating vertebroplasty to minimize the effect of expectations and to reduce the potential for bias in self-reporting of outcomes. Both trials applied stringent exclusion criteria so that the results are generalizable to the patient populations that are candidates for vertebroplasty. In both trials vertebroplasty procedures were performed by highly skilled interventionists. Multiple valid outcome measures including pain, physical, mental, and social function were employed to test the between group differences in outcomes.
Prior to these two trials, there were two open randomized trials in which vertebroplasty was compared with conservative medical treatment. In the first randomized trial, patients were allowed to cross over to the other arm and had to be stopped after two weeks due to the high numbers of patients crossing over. The other study did not allow cross over and recently published the results of 12 months follow-up.
The following is the summary of the results of these 4 trials:
Two blinded RCTs on vertebroplasty provide the highest level of evidence available to date. Results of these two trials are supported by findings of an open randomized trial with 12 months follow-up. Blinded RCTs showed:
No significant differences in pain scores of patients who received vertebroplasty and patients who received a sham procedure as measured at 3 days, 2 weeks and 1 month in one study and at 1 week, 1 month, 3 months, and 6 months in the other.
The observed differences in pain scores between the two groups were neither statistically significant nor clinically important at any time points.
The above findings were consistent with the findings of an open RCT in which patients were followed for 12 months. This study showed that improvement in pain was similar between the two groups at 3 months and were sustained to 12 months.
In the blinded RCTs, physical, mental, and social functioning were measured at the above time points using 4-5 of the following 7 instruments: RDQ, EQ-5D, SF-36 PCS, SF-36 MCS, AQoL, QUALEFFO, SOF-ADL
There were no significant differences in any of these measures between patients who received vertebroplasty and patients who received a sham procedure at any of the above time points (with a few exceptions in favour of control intervention).
These findings were also consistent with the findings of an open RCT which demonstrated no significant between group differences in scores of ED-5Q, SF-36 PCS, SF 36 MCS, DPQ, Barthel, and MMSE which measure physical, mental, and social functioning (with a few exceptions in favour of control intervention).
One small (n=34) open RCT with a two week follow-up detected a significantly higher improvement in pain scores at 1 day after the intervention in vertebroplasty group compared with conservative treatment group. However, at 2 weeks follow-up, this difference was smaller and was not statistically significant.
Conservative treatment was associated with fewer clinically important complications
Risk of new VCFs following vertebroplasty was higher than those in conservative treatment but it requires further investigation.
PMCID: PMC3377535  PMID: 23074396
22.  Antipsychotic medication for early episode schizophrenia 
Long-term treatment with antipsychotic medications in early episode schizophrenia spectrum disorders is common, but both short and long-term effects on the illness are unclear. There have been numerous suggestions that people with early episodes of schizophrenia appear to respond differently than those with multiple prior episodes. The number of episodes may moderate response to drug treatment.
To assess the effects of antipsychotic medication treatment on people with early episode schizophrenia spectrum disorders.
Search methods
We searched the Cochrane Schizophrenia Group register (July 2007) as well as references of included studies. We contacted authors of studies for further data.
Selection criteria
Studies with a majority of first and second episode schizophrenia spectrum disorders comparing initial antipsychotic medication treatment with placebo, milieu, or psychosocial treatment.
Data collection and analysis
Working independently, we critically appraised records from 681 studies, of which five studies met inclusion criteria. We calculated risk ratios (RR) and their 95% confidence intervals (CI) where possible. For continuous data, we calculated mean difference (MD). We calculated numbers needed to treat/harm (NNT/NNH) where appropriate.
Main results
Five studies (combined total n=998) met inclusion criteria. Four studies (n=724) provided leaving the study early data and results suggested that individuals treated with a typical antipsychotic medication are less likely to leave the study early than those treated with placebo (Chlorpromazine: 3 RCTs n=353, RR 0.4 CI 0.3 to 0.5, NNT 3.2, Fluphenaxine: 1 RCT n=240, RR 0.5 CI 0.3 to 0.8, NNT 5; Thioridazine: 1 RCT n=236, RR 0.44 CI 0.3 to 0.7, NNT 4.3, Trifulperazine: 1 RCT n=94, RR 0.96 CI 0.3 to 3.6). Two studies contributed data to assessment of adverse effects and present a general pattern of more frequent side effects among individuals treated with typical antipsychotic medications compared to placebo. One trial suggested a higher rehospitalisation rate for those receiving chlorpromazine compared to placebo (n=80, RR 2.29 CI 1.3 to 4.0, NNH 2.9). However, a higher attrition in the placebo group is likely to have introduced a survivor bias into this comparison, as this difference becomes non-significant in a sensitivity analysis on intent-to-treat participants (n=127, RR 1.69 CI 0.9 to 3.0). One study contributes data to a comparison of trifluoperazine to psychotherapy on long-term health in favour of the trifluoperazine group (n=92, MD 5.8 CI 1.6 to 0.0); however, data from this study are also likely to contain biases due to selection and attrition. One other study contributes data to a comparison of typical antipsychotic medication to psychosocial treatment on six-week outcome measures of global psychopathology (n=89, MD 0.01 CI −0.6 to 0.6) and global improvement (n=89, MD −0.03 CI −0.5 to 0.4), indicating no between-group differences. On the whole, there is very little useable data in the few studies meeting inclusion criteria.
Authors’ conclusions
With only a few studies meeting inclusion criteria, and with limited useable data in these studies, it is not possible to arrive at definitive conclusions. The preliminary pattern of evidence suggests that people with early episode schizophrenia treated with typical antipsychotic medications are less likely to leave the study early, but more likely to experience medication-related side effects. Data are too sparse to assess the effects of antipsychotic medication on outcomes in early episode schizophrenia.
PMCID: PMC4105695  PMID: 21678355
Antipsychotic Agents [adverse effects; *therapeutic use]; Chlorpromazine [therapeutic use]; Fluphenazine [therapeutic use]; Patient Dropouts; Randomized Controlled Trials as Topic; Schizophrenia [*drug therapy]; Thioridazine [therapeutic use]; Trifluoperazine [therapeutic use]; Humans
23.  Evidence for the Selective Reporting of Analyses and Discrepancies in Clinical Trials: A Systematic Review of Cohort Studies of Clinical Trials 
PLoS Medicine  2014;11(6):e1001666.
In a systematic review of cohort studies, Kerry Dwan and colleagues examine the evidence for selective reporting and discrepancies in analyses between journal publications and other documents for clinical trials.
Please see later in the article for the Editors' Summary
Most publications about selective reporting in clinical trials have focussed on outcomes. However, selective reporting of analyses for a given outcome may also affect the validity of findings. If analyses are selected on the basis of the results, reporting bias may occur. The aims of this study were to review and summarise the evidence from empirical cohort studies that assessed discrepant or selective reporting of analyses in randomised controlled trials (RCTs).
Methods and Findings
A systematic review was conducted and included cohort studies that assessed any aspect of the reporting of analyses of RCTs by comparing different trial documents, e.g., protocol compared to trial report, or different sections within a trial publication. The Cochrane Methodology Register, Medline (Ovid), PsycInfo (Ovid), and PubMed were searched on 5 February 2014. Two authors independently selected studies, performed data extraction, and assessed the methodological quality of the eligible studies. Twenty-two studies (containing 3,140 RCTs) published between 2000 and 2013 were included. Twenty-two studies reported on discrepancies between information given in different sources. Discrepancies were found in statistical analyses (eight studies), composite outcomes (one study), the handling of missing data (three studies), unadjusted versus adjusted analyses (three studies), handling of continuous data (three studies), and subgroup analyses (12 studies). Discrepancy rates varied, ranging from 7% (3/42) to 88% (7/8) in statistical analyses, 46% (36/79) to 82% (23/28) in adjusted versus unadjusted analyses, and 61% (11/18) to 100% (25/25) in subgroup analyses. This review is limited in that none of the included studies investigated the evidence for bias resulting from selective reporting of analyses. It was not possible to combine studies to provide overall summary estimates, and so the results of studies are discussed narratively.
Discrepancies in analyses between publications and other study documentation were common, but reasons for these discrepancies were not discussed in the trial reports. To ensure transparency, protocols and statistical analysis plans need to be published, and investigators should adhere to these or explain discrepancies.
Please see later in the article for the Editors' Summary
Editors' Summary
In the past, clinicians relied on their own experience when choosing the best treatment for their patients. Nowadays, they turn to evidence-based medicine—the systematic review and appraisal of trials, studies that investigate the benefits and harms of medical treatments in patients. However, evidence-based medicine can guide clinicians only if all the results from clinical trials are published in an unbiased and timely manner. Unfortunately, the results of trials in which a new drug performs better than existing drugs are more likely to be published than those in which the new drug performs badly or has unwanted side effects (publication bias). Moreover, trial outcomes that support the use of a new treatment are more likely to be published than those that do not support its use (outcome reporting bias). Recent initiatives—such as making registration of clinical trials in a trial registry (for example, a prerequisite for publication in medical journals—aim to prevent these biases, which pose a threat to informed medical decision-making.
Why Was This Study Done?
Selective reporting of analyses of outcomes may also affect the validity of clinical trial findings. Sometimes, for example, a trial publication will include a per protocol analysis (which considers only the outcomes of patients who received their assigned treatment) rather than a pre-planned intention-to-treat analysis (which considers the outcomes of all the patients regardless of whether they received their assigned treatment). If the decision to publish the per protocol analysis is based on the results of this analysis being more favorable than those of the intention-to-treat analysis (which more closely resembles “real” life), then “analysis reporting bias” has occurred. In this systematic review, the researchers investigate the selective reporting of analyses and discrepancies in randomized controlled trials (RCTs) by reviewing published studies that assessed selective reporting of analyses in groups (cohorts) of RCTs and discrepancies in analyses of RCTs between different sources (for example, between the protocol in a trial registry and the journal publication) or different sections of a source. A systematic review uses predefined criteria to identify all the research on a given topic.
What Did the Researchers Do and Find?
The researchers identified 22 cohort studies (containing 3,140 RCTs) that were eligible for inclusion in their systematic review. All of these studies reported on discrepancies between the information provided by the RCTs in different places, but none investigated the evidence for analysis reporting bias. Several of the cohort studies reported, for example, that there were discrepancies in the statistical analyses included in the different documents associated with the RCTs included in their analysis. Other types of discrepancies reported by the cohort studies included discrepancies in the reporting of composite outcomes (an outcome in which multiple end points are combined) and in the reporting of subgroup analyses (investigations of outcomes in subgroups of patients that should be predefined in the trial protocol to avoid bias). Discrepancy rates varied among the RCTs according to the types of analyses and cohort studies considered. Thus, whereas in one cohort study discrepancies were present in the statistical test used for the analysis of the primary outcome in only 7% of the included studies, they were present in the subgroup analyses of all the included studies.
What Do These Findings Mean?
These findings indicate that discrepancies in analyses between publications and other study documents such as protocols in trial registries are common. The reasons for these discrepancies in analyses were not discussed in trial reports but may be the result of reporting bias, errors, or legitimate departures from a pre-specified protocol. For example, a statistical analysis that is not specified in the trial protocol may sometimes appear in a publication because the journal requested its inclusion as a condition of publication. The researchers suggest that it may be impossible for systematic reviewers to distinguish between these possibilities simply by looking at the source documentation. Instead, they suggest, it may be necessary for reviewers to contact the trial authors. However, to make selective reporting of analyses more easily detectable, they suggest that protocols and analysis plans should be published and that investigators should be required to stick to these plans or explain any discrepancies when they publish their trial results. Together with other initiatives, this approach should help improve the quality of evidence-based medicine and, as a result, the treatment of patients.
Additional Information
Please access these websites via the online version of this summary at
Wikipedia has pages on evidence-based medicine, on systematic reviews, and on publication bias (note: Wikipedia is a free online encyclopedia that anyone can edit; available in several languages) provides information about the US National Institutes of Health clinical trial registry, including background information about clinical trials
The Cochrane Collaboration is a global independent network of health practitioners, researchers, patient advocates, and others that aims to promote evidence-informed health decision-making by producing high-quality, relevant, accessible systematic reviews and other synthesized research evidence; the Cochrane Handbook for Systematic Reviews of Interventions describes the preparation of systematic reviews in detail
PLOS Medicine recently launched a Reporting Guidelines Collection, an open-access collection of reporting guidelines, commentary, and related research on guidelines from across PLOS journals that aims to help advance the efficiency, effectiveness, and equitability of the dissemination of biomedical information
PMCID: PMC4068996  PMID: 24959719
24.  Functional Brain Imaging 
Executive Summary
The objective of this analysis is to review a spectrum of functional brain imaging technologies to identify whether there are any imaging modalities that are more effective than others for various brain pathology conditions. This evidence-based analysis reviews magnetoencephalography (MEG), magnetic resonance spectroscopy (MRS), positron emission tomography (PET), and functional magnetic resonance imaging (fMRI) for the diagnosis or surgical management of the following conditions: Alzheimer’s disease (AD), brain tumours, epilepsy, multiple sclerosis (MS), and Parkinson’s disease (PD).
Clinical Need: Target Population and Condition
Alzheimer’s disease is a progressive, degenerative, neurologic condition characterized by cognitive impairment and memory loss. The Canadian Study on Health and Aging estimated that there will be 97,000 incident cases (about 60,000 women) of dementia (including AD) in Canada in 2006.
In Ontario, there will be an estimated 950 new cases and 580 deaths due to brain cancer in 2006. Treatments for brain tumours include surgery and radiation therapy. However, one of the limitations of radiation therapy is that it damages tissue though necrosis and scarring. Computed tomography (CT) and magnetic resonance imaging (MRI) may not distinguish between radiation effects and resistant tissue, creating a potential role for functional brain imaging.
Epilepsy is a chronic disorder that provokes repetitive seizures. In Ontario, the rate of epilepsy is estimated to be 5 cases per 1,000 people. Most people with epilepsy are effectively managed with drug therapy; but about 50% do not respond to drug therapy. Surgical resection of the seizure foci may be considered in these patients, and functional brain imaging may play a role in localizing the seizure foci.
Multiple sclerosis is a progressive, inflammatory, demyelinating disease of the central nervous system (CNS). The cause of MS is unknown; however, it is thought to be due to a combination of etiologies, including genetic and environmental components. The prevalence of MS in Canada is 240 cases per 100,000 people.
Parkinson’s disease is the most prevalent movement disorder; it affects an estimated 100,000 Canadians. Currently, the standard for measuring disease progression is through the use of scales, which are subjective measures of disease progression. Functional brain imaging may provide an objective measure of disease progression, differentiation between parkinsonian syndromes, and response to therapy.
The Technology Being Reviewed
Functional Brain Imaging
Functional brain imaging technologies measure blood flow and metabolism. The results of these tests are often used in conjunction with structural imaging (e.g., MRI or CT). Positron emission tomography and MRS identify abnormalities in brain tissues. The former measures abnormalities through uptake of radiotracers in the brain, while the latter measures chemical shifts in metabolite ratios to identify abnormalities. The potential role of functional MRI (fMRI) is to identify the areas of the brain responsible for language, sensory and motor function (sensorimotor cortex), rather than identifying abnormalities in tissues. Magnetoencephalography measures magnetic fields of the electric currents in the brain, identifying aberrant activity. Magnetoencephalography may have the potential to localize seizure foci and to identify the sensorimotor cortex, visual cortex and auditory cortex.
In terms of regulatory status, MEG and PET are licensed by Health Canada. Both MRS and fMRI use a MRI platform; thus, they do not have a separate licence from Health Canada. The radiotracers used in PET scanning are not licensed by Health Canada for general use but can be used through a Clinical Trials Application.
Review Strategy
The literature published up to September 2006 was searched in the following databases: MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, EMBASE, Cochrane Database of Systematic Reviews, CENTRAL, and International Network of Agencies for Health Technology Assessment (INAHTA). The database search was supplemented with a search of relevant Web sites and a review of the bibliographies of selected papers.
General inclusion criteria were applied to all conditions. Those criteria included the following:
Full reports of systematic reviews, randomized controlled trials (RCTs), cohort-control studies, prospective cohort studies (PCS’), and retrospective studies.
Sample sizes of at least 20 patients (≥ 10 with condition being reviewed).
English-language studies.
Human studies.
Any age.
Studying at least one of the following: fMRI, PET, MRS, or MEG.
Functional brain imaging modality must be compared with a clearly defined reference standard.
Must report at least one of the following outcomes: sensitivity, specificity, accuracy, positive predictive value (PPV), receiver operating characteristic curve, outcome measuring impact on diagnostic testing, treatment, patient health, or cost.
Summary of Findings
There is evidence to indicate that PET can accurately diagnose AD; however, at this time, there is no evidence to suggest that a diagnosis of AD with PET alters the clinical outcomes of patients.
The addition of MRS or O-(2-18F-Fluoroethyl)-L-Tyrosine (FET)-PET to gadolinium (Gd)-enhanced MRI for distinguishing malignant from benign tumours during primary diagnosis may provide a higher specificity than Gd-enhanced MRI alone. The clinical utility of additional imaging in patients to distinguish malignant from benign tumours is unclear, because patients with a suspected brain tumour will likely undergo a biopsy despite additional imaging results.
The addition of MRS, FET-PET, or MRI T2 to Gd-enhanced MRI for the differentiation of recurrence from radiation necrosis may provide a higher specificity than Gd-enhanced MRI alone. The clinical utility of additional imaging in patients with a suspected recurrence is in the monitoring of patients. Based on the evidence available, it is unclear if one of the imaging modalities (MRS, FET-PET, or MRI T2) offers significantly improved specificity over another.
There may be a role for fMRI in the identification of surgical candidates for tumour resection; however, this requires further research.
Based on the studies available, it is unclear if MEG has similar accuracy in localizing seizure foci to intracranial electroencephalogram (ICEEG). More high-quality research is needed to establish whether there is a difference in accuracy between MEG and ICEEG.
The results of the studies comparing PET to noninvasive electroencephalogram (EEG) did not demonstrate that PET was more accurate at localizing seizure foci; however, there may be some specific conditions, such as tuberous sclerosis, where PET may be more accurate than noninvasive EEG.
There may be some clinical utility for MEG or fMRI in presurgical functional mapping; however, this needs further investigation involving comparisons with other modalities. The clinical utility of MRS has yet to be established for patients with epilepsy.
Positron emission tomography has high sensitivity and specificity in the diagnosis of PD and the differential diagnosis of parkinsonian syndromes; however, it is unclear at this time if the addition of PET in the diagnosis of these conditions contributes to the treatment and clinical outcomes of patients.
There is limited clinical utility of functional brain imaging in the management of patients with MS at this time. Diagnosis of MS is established through clinical history, evoked potentials, and MRI. Magnetic resonance imaging can identify the multifocal white lesions and other structural characteristics of MS.
PMCID: PMC3379170  PMID: 23074493
25.  Definitions and methods of measuring and reporting on injurious falls in randomised controlled fall prevention trials: a systematic review 
The standardisation of the assessment methodology and case definition represents a major precondition for the comparison of study results and the conduction of meta-analyses. International guidelines provide recommendations for the standardisation of falls methodology; however, injurious falls have not been targeted. The aim of the present article was to review systematically the range of case definitions and methods used to measure and report on injurious falls in randomised controlled trials (RCTs) on fall prevention.
An electronic literature search of selected comprehensive databases was performed to identify injurious falls definitions in published trials. Inclusion criteria were: RCTs on falls prevention published in English, study population ≥ 65 years, definition of injurious falls as a study endpoint by using the terms "injuries" and "falls".
The search yielded 2089 articles, 2048 were excluded according to defined inclusion criteria. Forty-one articles were included. The systematic analysis of the methodology applied in RCTs disclosed substantial variations in the definition and methods used to measure and document injurious falls. The limited standardisation hampered comparability of study results. Our results also highlight that studies which used a similar, standardised definition of injurious falls showed comparable outcomes.
No standard for defining, measuring, and documenting injurious falls could be identified among published RCTs. A standardised injurious falls definition enhances the comparability of study results as demonstrated by a subgroup of RCTs used a similar definition. Recommendations for standardising the methodology are given in the present review.
PMCID: PMC3388463  PMID: 22510239
Systematic review; Injurious falls; Elderly; Fall-related outcomes; Fall prevention trials

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