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1.  Prognosis in patients with recent onset low back pain in Australian primary care: inception cohort study 
Objective To estimate the one year prognosis and identify prognostic factors in cases of recent onset low back pain managed in primary care.
Design Cohort study with one year follow-up.
Setting Primary care clinics in Sydney, Australia.
Participants An inception cohort of 973 consecutive primary care patients (mean age 43.3, 54.8% men) with non-specific low back pain of less than two weeks’ duration recruited from the clinics of 170 general practitioners, physiotherapists, and chiropractors.
Main outcome measures Participants completed a baseline questionnaire and were contacted six weeks, three months, and 12 months after the initial consultation. Recovery was assessed in terms of return to work, return to function, and resolution of pain. The association between potential prognostic factors and time to recovery was modelled with Cox regression.
Results The follow-up rate over the 12 months was more than 97%. Half of those who reduced their work status at baseline had returned to previous work status within 14 days (95% confidence interval 11 to 17 days) and 83% had returned to previous work status by three months. Disability (median recovery time 31 days, 25 to 37 days) and pain (median 58 days, 52 to 63 days) took much longer to resolve. Only 72% of participants had completely recovered 12 months after the baseline consultation. Older age, compensation cases, higher pain intensity, longer duration of low back pain before consultation, more days of reduced activity because of lower back pain before consultation, feelings of depression, and a perceived risk of persistence were each associated with a longer time to recovery.
Conclusions In this cohort of patients with acute low back pain in primary care, prognosis was not as favourable as claimed in clinical practice guidelines. Recovery was slow for most patients. Nearly a third of patients did not recover from the presenting episode within a year.
PMCID: PMC2483884  PMID: 18614473
2.  Prognosis of acute low back pain: design of a prospective inception cohort study 
Clinical guidelines generally portray acute low back pain as a benign and self-limiting condition. However, evidence about the clinical course of acute low back pain is contradictory and the risk of subsequently developing chronic low back pain remains uncertain. There are few high quality prognosis studies and none that have measured pain, disability and return to work over a 12 month period. This study aims to provide the first estimates of the one year prognosis of acute low back pain (pain of less than 2 weeks duration) in patients consulting primary care practitioners. A secondary aim is to identify factors that are associated with the prognosis of low back pain.
The study is a prospective inception cohort study. Consecutive patients consulting general medical practitioners, physiotherapists and chiropractors in the Sydney metropolitan region will complete a baseline questionnaire regarding their back pain. Subsequently these patients will be followed up by telephone 6 weeks, 3 months and 12 months after the initial consultation. Patients will be considered to have recovered from the episode of back pain if they have no pain and no limitation of activity, and have returned to pre-injury work status. Life tables will be generated to determine the one year prognosis of acute low back pain. Prognostic factors will be assessed using Cox regression.
This study will provide the first estimates of the one year prognosis of acute low back pain in a representative sample of primary care patients.
PMCID: PMC1543628  PMID: 16790069
3.  Prognosis for patients with chronic low back pain: inception cohort study 
Objectives To describe the course of chronic low back pain in an inception cohort and to identify prognostic markers at the onset of chronicity.
Design Inception cohort study with one year follow-up.
Setting Primary care clinics in Sydney, Australia.
Participants The study sample was a subcohort of an inception cohort of 973 consecutive patients presenting to primary care with acute low back pain (<2 weeks’ duration). 406 participants whose pain persisted for three months formed the inception cohort of patients with chronic low back pain.
Main outcome measures Outcomes and putative predictors measured at initial presentation, onset of chronicity (study entry), and follow-up at nine and 12 months. Recovery was determined from measures of pain intensity, disability, and work status. The association between potential prognostic factors and time to recovery was modelled with Cox regression.
Results Completeness of follow-up was 97% of total person time for all outcomes. The cumulative probability of being pain-free was 35% at nine months and 42% at 12 months and for complete recovery was 35% at nine months and 41% at 12 months. Of the 259 participants who had not recovered from pain related disability at entry to the chronic study, 47% had recovered by 12 months. Previous sick leave due to low back pain, high disability levels or high pain intensity at onset of chronicity, low levels of education, greater perceived risk of persistent pain, and being born outside Australia were associated with delayed recovery.
Conclusion More than one third of patients with recent onset, non-radicular chronic low back pain recover within 12 months. The prognosis is less favourable for those who have taken previous sick leave for low back pain, have high disability levels or high pain intensity at onset of chronic low back pain, have lower education, perceive themselves as having a high risk of persistent pain, and were born outside Australia.
PMCID: PMC2758336  PMID: 19808766
4.  Prognosis of chronic low back pain: design of an inception cohort study 
Although clinical guidelines generally portray chronic low back pain as a condition with a poor prognosis this portrayal is based on studies of potentially unrepresentative survival cohorts. The aim of this study is to describe the prognosis of an inception cohort of people with chronic low back pain presenting for primary care.
The study will be an inception cohort study with one year follow-up. Participants are drawn from a cohort of consecutive patients presenting with acute low back pain (less than 2 weeks duration) to primary care clinics in Sydney, Australia. Those patients who continue to experience pain at three months, and are therefore classified as having chronic back pain, are invited to participate in the current study. The cohort will be followed up by telephone at baseline, 9 months and 12 months after being diagnosed with chronic low back pain. Recovery from low back pain will be measured by sampling three different outcomes: pain intensity, interference with function due to pain, and work status. Life tables will be generated to determine the one year prognosis of chronic low back pain. Prognostic factors will be assessed using Cox regression.
This study will determine the prognosis of chronic non-specific low back pain in a representative cohort of patients sourced from primary care. The results of this study will improve understanding of chronic low back pain, allowing clinicians to provide more accurate prognostic information to their patients.
PMCID: PMC1800846  PMID: 17288586
5.  Expectations for Recovery Important in the Prognosis of Whiplash Injuries 
PLoS Medicine  2008;5(5):e105.
Individuals' expectations on returning to work after an injury have been shown to predict the duration of time that a person with work-related low back pain will remain on benefits; individuals with lower recovery expectations received benefits for a longer time than those with higher expectations. The role of expectations in recovery from traumatic neck pain, in particular whiplash-associated disorders (WAD), has not been assessed to date to our knowledge. The aim of this study was to investigate if expectations for recovery are a prognostic factor after experiencing a WAD.
Methods and Findings
We used a prospective cohort study composed of insurance claimants in Sweden. The participants were car occupants who filed a neck injury claim (i.e., for WAD) to one of two insurance companies between 15 January 2004 and 12 January 2005 (n = 1,032). Postal questionnaires were completed shortly (average 23 d) after the collision and then again 6 mo later. Expectations for recovery were measured with a numerical rating scale (NRS) at baseline, where 0 corresponds to “unlikely to make a full recovery” and 10 to “very likely to make a full recovery.” The scale was reverse coded and trichotomised into NRS 0, 1–4, and 5–10. The main outcome measure was self-perceived disability at 6 mo postinjury, measured with the Pain Disability Index, and categorised into no/low, moderate, and high disability. Multivariable polytomous logistic regression was used for the analysis. There was a dose response relationship between recovery expectations and disability. After controlling for severity of physical and mental symptoms, individuals who stated that they were less likely to make a full recovery (NRS 5–10), were more likely to have a high disability compared to individuals who stated that they were very likely to make a full recovery (odds ratio [OR] 4.2 [95% confidence interval (CI) 2.1 to 8.5]. For the intermediate category (NRS 1–4), the OR was 2.1 (95% CI 1.2 to 3.2). Associations between expectations and disability were also found among individuals with moderate disability.
Individuals' expectations for recovery are important in prognosis, even after controlling for symptom severity. Interventions designed to increase patients' expectations may be beneficial and should be examined further in controlled studies.
Lena Holm and colleagues show that in people who had a whiplash injury after a car crash there was an association between expectation of disability and actual disability six months later.
Editors' Summary
The disability associated with injury is a major source of distress for patients, and can be costly to the health care system and employers when persons fail to recover quickly and are unable to return to work. Finding ways to help people recover quickly and get back to optimal health is important. Some of the most common injuries causing disability and time off work result from whiplash—the sudden hyperextension or “whipping” of the neck, which can occur from a motor vehicle crash. It has long been recognized that psychological factors (such as the ability to cope, how “in control” one feels about one's life) are as important as physical symptoms in how disabling an injury can be. There is now growing evidence that a person's feelings about their ability to recover from injury plays a part in actual recovery. Studies from Europe and North America have shown with conditions like low back pain and minor head injury that a patient's feelings about the possibility of getting better are related to how well they do. Less is known about how important these psychological factors are in recovery from disorders due to whiplash associated disorders.
Why Was This Study Done?
The authors wanted to find out whether there was a relationship between people's expectations for their recovery from whiplash associated disorders and their actual recovery six months later. So, for example, they wondered if a person with whiplash who felt they were very unlikely to recover from their injury, actually did not recover (and vice versa).
What Did the Researchers Do and Find?
The authors had access to an unusual set of health information—insurance claims by people who had been involved in car collisions to two insurance companies in Sweden. They identified about 1,000 adult insurance claimants over one year and mailed them a questionnaire that asked for details about the collision as well as information about the claimant: their demographic profile, health history, and the types of pain and symptoms experienced since the crash. The questionnaire also asked the claimant how likely they thought they were to make a full recovery from their injuries.
For those who said they had whiplash associated disorders, the authors followed up with another questionnaire six months later, which asked for information about any disability, pain, or other symptoms that the claimant was still experiencing because of the injury. Of those who had completed the first questionnaire, 82% were followed up.
Only about a quarter of claimants with whiplash associated disorders said they expected to make a full recovery. Perhaps not surprisingly, those with only mild pain, compared to those with intense pain, were more likely to think so. Persons who said they were less likely to make a full recovery were four times more likely to report high levels of disability six months later. Even for persons (or individuals) people with moderate levels of disability six months after injury, their expectations for recovery were similarly linked to how well they did: the lower the expectations for recovery, the higher the disability. These findings were true even after taking into account how severe signs and symptoms the person had, and how well the person was coping psychologically.
What Do These Findings Mean?
The findings indicate that those with the lowest expectations for recovery after their whiplash injury will have the poorest recovery, and those with the highest expectations will have the best recovery. They also suggest that a patient's expectations about getting better are as important as his or her physical symptoms. The authors say that the more we can influence patients to believe they will make a full recovery, the better chance they will have to recover completely. This means that it may be beneficial for healthcare providers to give support and/or education to patients with whiplash associated disorders that increases their positive feelings toward recovery. The authors call for more studies into whether these types of targeted interventions would be of benefit.
Additional Information
Please access these Web sites via the online version of this summary at
Information about research on injuries and rehabilitation can be found at the Web sites of organisations devoted to studying the health of workers, such as the Institute for Work and Health in Canada, the Finnish Institute of Occupational Health, and the US National Institute for Occupational Safety and Health
The Wikipedia entry for medical aspects of whiplash describes the four grades of whiplash disorder, but does not cover the debate about the credibility of whiplash disorder (please note that Wikipedia is an online encyclopedia that anyone can edit)
The Sjukvardsradgivningen Web site provides information about whiplash-related disorders, common signs and symptoms, recovery and prognosis, and treatments (in Swedish)
PMCID: PMC2375948  PMID: 18479182
6.  Clinical course and prognostic factors in acute low back pain: an inception cohort study in primary care practice. 
BMJ : British Medical Journal  1994;308(6928):577-580.
OBJECTIVE--To describe the natural course of recent acute low back pain in terms of both morbidity (pain, disability) and absenteeism from work and to evaluate the prognostic factors for these outcomes. DESIGN--Inception cohort study. SETTING--Primary care. PATIENTS--103 patients with acute localised non-specific back pain lasting less than 72 hours. MAIN OUTCOME MEASURES--Complete recovery (disappearance of both pain and disability) and return to work. RESULTS--90% of patients recovered within two weeks and only two developed chronic low back pain. Only 49 of 100 patients for whom data were available had bed rest and 40% of 75 employed patients lost no time from work. Proportional hazards regression analysis showed that previous chronic episodes of low back pain, initial disability level, initial pain worse when standing, initial pain worse when lying, and compensation status were significantly associated with delayed episode recovery. These factors were also related to absenteeism from work. Absenteeism from work was also influenced by job satisfaction and gender. CONCLUSIONS--The recovery rate from acute low back pain was much higher than reported in other studies. Those studies, however, did not investigate groups of patients enrolled shortly after the onset of symptoms and often mixed acute low back pain patients with patients with exacerbations of chronic pain or sciatica. Several sociodemographic and clinical factors were of prognostic value in acute low back pain. Factors which influenced the outcome in terms of episode recovery (mainly physical severity factors) were only partly predictive of absenteeism from work. Time off work and return to work depended more on sociodemographic and job related influences.
PMCID: PMC2539597  PMID: 8148683
7.  The Prognosis of Acute Low Back Pain in Primary Care in the U.S. A 2-Year Prospective Cohort Study 
Spine  2012;37(8):678-684.
Study Design
Prospective cohort study
to assess the prognosis of patients presenting with acute low back pain (LBP) in a primary care setting in the U.S.
Summary of Background Data
Practice guidelines for acute LBP based on return-to-work outcomes underestimate the development of chronic pain in the primary care setting. Due to differences in inclusion criteria, chronic pain definitions and national health systems, prognostic cohort studies have reported a wide range of results limiting interpretation and generalization. Current data from carefully designed prognostic studies of acute LBP are lacking for the U.S. primary care system.
Members of a large health service organization were enrolled after seeking medical care for acute LBP, with or without sciatica, of up to 30 days duration, with no prior episode in the past 12 months and no history of spine surgery. We conducted phone interviews at baseline, six months and two years. Based on receiver operating characteristic analyses, a combination of global perceived recovery with pain intensity was used as primary outcome for chronic pain. Recurrence and multiple secondary outcomes were assessed to allow for comparison with other studies.
605 patients had an average pain intensity of 5.6 (numeric rating scale 0–10) and disability of 15.8 (Roland Morris scale 0–24). Eight percent had declared sick leave between pain onset and baseline interview. 13% of 521 patients (86% follow-up) suffered from chronic pain at six months and 19% of 443 patients at 2 years. At six months, 54% had experienced at least one LBP recurrence, and 47% in the subsequent 18 months.
The prognosis of strictly-defined acute LBP, with or without sciatica, is less favorable than commonly stated in practice guidelines based on failure to return to work. Broad initiatives to develop new means for the primary and secondary prevention of recurrent and chronic LBP are urgently needed.
PMCID: PMC3335773  PMID: 22504516
Low Back Pain; Prognosis; Acute Pain; Chronic Pain
8.  A clinical return-to-work rule for patients with back pain 
Tools for early identification of workers with back pain who are at high risk of adverse occupational outcome would help concentrate clinical attention on the patients who need it most, while helping reduce unnecessary interventions (and costs) among the others. This study was conducted to develop and validate clinical rules to predict the 2-year work disability status of people consulting for nonspecific back pain in primary care settings.
This was a 2-year prospective cohort study conducted in 7 primary care settings in the Quebec City area. The study enrolled 1007 workers (participation, 68.4% of potential participants expected to be eligible) aged 18–64 years who consulted for nonspecific back pain associated with at least 1 day's absence from work. The majority (86%) completed 5 telephone interviews documenting a large array of variables. Clinical information was abstracted from the medical files. The outcome measure was “return to work in good health” at 2 years, a variable that combined patients' occupational status, functional limitations and recurrences of work absence. Predictive models of 2-year outcome were developed with a recursive partitioning approach on a 40% random sample of our study subjects, then validated on the rest.
The best predictive model included 7 baseline variables (patient's recovery expectations, radiating pain, previous back surgery, pain intensity, frequent change of position because of back pain, irritability and bad temper, and difficulty sleeping) and was particularly efficient at identifying patients with no adverse occupational outcome (negative predictive value 78%– 94%).
A clinical prediction rule accurately identified a large proportion of workers with back pain consulting in a primary care setting who were at a low risk of an adverse occupational outcome.
PMCID: PMC558170  PMID: 15939915
9.  Endovascular Radiofrequency Ablation for Varicose Veins 
Executive Summary
The objective of the MAS evidence review was to conduct a systematic review of the available evidence on the safety, effectiveness, durability and cost–effectiveness of endovascular radiofrequency ablation (RFA) for the treatment of primary symptomatic varicose veins.
The Ontario Health Technology Advisory Committee (OHTAC) met on August 26th, 2010 to review the safety, effectiveness, durability, and cost-effectiveness of RFA for the treatment of primary symptomatic varicose veins based on an evidence-based review by the Medical Advisory Secretariat (MAS).
Clinical Condition
Varicose veins (VV) are tortuous, twisted, or elongated veins. This can be due to existing (inherited) valve dysfunction or decreased vein elasticity (primary venous reflux) or valve damage from prior thrombotic events (secondary venous reflux). The end result is pooling of blood in the veins, increased venous pressure and subsequent vein enlargement. As a result of high venous pressure, branch vessels balloon out leading to varicosities (varicose veins).
Symptoms typically affect the lower extremities and include (but are not limited to): aching, swelling, throbbing, night cramps, restless legs, leg fatigue, itching and burning. Left untreated, venous reflux tends to be progressive, often leading to chronic venous insufficiency (CVI). A number of complications are associated with untreated venous reflux: including superficial thrombophlebitis as well as variceal rupture and haemorrhage. CVI often results in chronic skin changes referred to as stasis dermatitis. Stasis dermatitis is comprised of a spectrum of cutaneous abnormalities including edema, hyperpigmentation, eczema, lipodermatosclerosis and stasis ulceration. Ulceration represents the disease end point for severe CVI. CVI is associated with a reduced quality of life particularly in relation to pain, physical function and mobility. In severe cases, VV with ulcers, QOL has been rated to be as bad or worse as other chronic diseases such as back pain and arthritis.
Lower limb VV is a very common disease affecting adults – estimated to be the 7th most common reason for physician referral in the US. There is a very strong familial predisposition to VV. The risk in offspring is 90% if both parents affected, 20% when neither affected and 45% (25% boys, 62% girls) if one parent affected. The prevalence of VV worldwide ranges from 5% to 15% among men and 3% to 29% among women varying by the age, gender and ethnicity of the study population, survey methods and disease definition and measurement. The annual incidence of VV estimated from the Framingham Study was reported to be 2.6% among women and 1.9% among men and did not vary within the age range (40-89 years) studied.
Approximately 1% of the adult population has a stasis ulcer of venous origin at any one time with 4% at risk. The majority of leg ulcer patients are elderly with simple superficial vein reflux. Stasis ulcers are often lengthy medical problems and can last for several years and, despite effective compression therapy and multilayer bandaging are associated with high recurrence rates. Recent trials involving surgical treatment of superficial vein reflux have resulted in healing and significantly reduced recurrence rates.
Endovascular Radiofrequency Ablation for Varicose Veins
RFA is an image-guided minimally invasive treatment alternative to surgical stripping of superficial venous reflux. RFA does not require an operating room or general anaesthesia and has been performed in an outpatient setting by a variety of medical specialties including surgeons and interventional radiologists. Rather than surgically removing the vein, RFA works by destroying or ablating the refluxing vein segment using thermal energy delivered through a radiofrequency catheter.
Prior to performing RFA, color-flow Doppler ultrasonography is used to confirm and map all areas of venous reflux to devise a safe and effective treatment plan. The RFA procedure involves the introduction of a guide wire into the target vein under ultrasound guidance followed by the insertion of an introducer sheath through which the RFA catheter is advanced. Once satisfactory positioning has been confirmed with ultrasound, a tumescent anaesthetic solution is injected into the soft tissue surrounding the target vein along its entire length. This serves to anaesthetize the vein, insulate the heat from damaging adjacent structures, including nerves and skin and compresses the vein increasing optimal contact of the vessel wall with the electrodes or expanded prongs of the RF device. The RF generator is then activated and the catheter is slowly pulled along the length of the vein. At the end of the procedure, hemostasis is then achieved by applying pressure to the vein entry point.
Adequate and proper compression stockings and bandages are applied after the procedure to reduce the risk of venous thromboembolism and to reduce postoperative bruising and tenderness. Patients are encouraged to walk immediately after the procedure. Follow-up protocols vary, with most patients returning 1 to 3 weeks later for an initial follow-up visit. At this point, the initial clinical result is assessed and occlusion of the treated vessels is confirmed with ultrasound. Patients often have a second follow-up visit 1 to 3 months following RFA at which time clinical evaluation and ultrasound are repeated. If required, additional procedures such as phlebectomy or sclerotherapy may be performed during the RFA procedure or at any follow-up visits.
Regulatory Status
The Closure System® radiofrequency generator for endovascular thermal ablation of varicose veins was approved by Health Canada as a class 3 device in March 2005, registered under medical device license 67865. The RFA intravascular catheter was approved by Health Canada in November 2007 for the ClosureFast catheter, registered under medical device license 16574. The Closure System® also has regulatory approvals in Australia, Europe (CE Mark) and the United States (FDA clearance). In Ontario, RFA is not an insured service and is currently being introduced in private clinics.
Literature Search
The MAS evidence–based review was performed to support public financing decisions. The literature search was performed on March 9th, 2010 using standard bibliographic databases for studies published up until March, 2010.
Inclusion Criteria
English language full-reports and human studies Original reports with defined study methodologyReports including standardized measurements on outcome events such as technical success, safety, effectiveness, durability, quality of life or patient satisfaction Reports involving RFA for varicose veins (great or small saphenous veins)Randomized controlled trials (RCTs), systematic reviews and meta-analysesCohort and controlled clinical studies involving ≥ 1 month ultrasound imaging follow-up
Exclusion Criteria
Non systematic reviews, letters, comments and editorials Reports not involving outcome events such as safety, effectiveness, durability, or patient satisfaction following an intervention with RFAReports not involving interventions with RFA for varicose veinsPilot studies or studies with small samples (< 50 subjects)
Summary of Findings
The MAS evidence search on the safety and effectiveness of endovascular RFA ablation of VV identified the following evidence: three HTAs, nine systematic reviews, eight randomized controlled trials (five comparing RFA to surgery and three comparing RFA to ELT), five controlled clinical trials and fourteen cohort case series (four were multicenter registry studies).
The majority (12⁄14) of the cohort studies (3,664) evaluating RFA for VV involved treatment with first generation RFA catheters and the great saphenous vein (GSV) was the target vessel in all studies. Major adverse events were uncommonly reported and the overall pooled major adverse event rate extracted from the cohort studies was 2.9% (105⁄3,664). Imaging defined treatment effectiveness of vein closure rates were variable ranging from 68% to 96% at post-operative follow-up. Vein ablation rate at 6-month follow-up was reported in four studies with rates close to 90%. Only one study reported vein closure rates at 2 years but only for a minority of the eligible cases. The two studies reporting on RFA ablation with the more efficient second generation catheters involved better follow-up and reported higher ablation rates close to 100% at 6-month follow-up with no major adverse events. A large prospective registry trial that recruited over 1,000 patients at thirty-four largely European centers reported on treatment success in six overlapping reports on selected patient subgroups at various follow-up points up to 5 year. However, the follow-up for eligible recruited patients at all time points was low resulting in inadequate estimates of longer term treatment efficacy.
The overall level of evidence of randomized trials comparing RFA with surgical ligation and vein stripping (n = 5) was graded as low to moderate. In all trials RFA ablation was performed with first generation catheters in the setting of the operating theatre under general anaesthesia, usually without tumescent anaesthesia. Procedure times were significantly longer after RFA than surgery. Recovery after treatment was significantly quicker after RFA both with return to usual activity and return to work with on average a one week less of work loss. Major adverse events occurring after surgery were higher [(1.8% (n=4) vs. 0.4% (n = 1) than after RFA but not significantly. Treatment effectiveness measured by imaging defined vein absence or vein closure was comparable in the two treatment groups. Significant improvements in vein symptoms and quality of life over baseline were reported for both treatment groups. Improvements in these outcomes were significantly greater in the RFA group than the surgery group in the peri-operative period but not in later follow-up. Follow-up in these trials was inadequate to evaluate longer term recurrence for either treatment. Patient satisfaction was reported to be high for both treatments but was higher for RFA.
The studies comparing endovascular treatment approaches for VV (RFA and ELT) were more limited. Three RCT studies compared RFA (two with the second generation catheter) with ELT but mainly focused on peri-procedural outcomes such as pain, complications and recovery. Vein ablation rates were not evaluated in the trials, except for one small trial involving bilateral VV. Pain responses in patients undergoing ablation were extremely variable and up to 2 weeks, mean pain levels were significantly less with RFA than ELT ablation but differences were not significant at one month. Recovery, evaluated as return to usual activity or return to work, however, was similar in the treatment groups. Vein symptom and QOL improvements were improved in both groups but were significantly better in the RFA group than the ELT group at 2 weeks, but not at one month. Vein ablation rates were evaluated in several controlled clinical studies comparing the treatments between centers or within centers between individuals or over time. Comparisons in these studies were inconsistent with vein ablation rates for RFA reported to be similar to, higher than and lower than those with ELT.
Economic Analysis
RFA and surgical vein stripping, the main comparator reimbursed by the public system, are comparable in clinical benefits. Hence a cost-analysis was conducted to identify the differences in resources and costs between both procedures and a budgetary impact analysis (BIA) was conducted to project costs over a 5- year period in the province of Ontario. The target population of this economic analysis was patients with symptomatic varicose veins and the primary analytic perspective was that of the Ministry of Health and Long-Term Care.
The average case cost (based on Ontario hospital costs and medical resources) for surgical vein stripping was estimated to be $1,799. In order to calculate a procedural cost for RFA it was assumed that the hospital cost and physician labour fees, excluding anaesthesia and surgical assistance, were the same as vein stripping surgery. The manufacturer also provided details on the generator with a capital cost of $27,500 and a lifespan of 5 years and the disposables (catheter, sheath, guidewire) with a cost of $673 per case. The average case cost for RFA was therefore estimated to be $1,356. One-way sensitivity analysis was also conducted with hospital cost of RFA varied to 60% that of vein stripping surgery (average cost per case = $627.08) to calculate an impact to the province.
Historical volumes of vein stripping surgeries in Ontario were used to project surgeries in a linear fashion up to five years into the future. Volumes for RFA and ELT were calculated based on share capture from the surgery market based on discussion with clinical expert opinion and existing private data based on discussion with the manufacturer. RFA is expected to compete with ELT and capture some of the market. If ELT is reimbursed by the public sector then numbers will continue to increase from previous private data and share capture from the conventional surgical treatment market. Therefore, RFA cases will also increase since it will be capturing a share of the ELT market. A budget impact to the province was then calculated by multiplying volumes by the cost of the procedure.
RFA is comparable in clinical benefits to vein stripping surgery. It has the extra upfront cost of the generator and cost per case for disposables but does not require an operating theater, anaesthetist or surgical assistant fees. The impact to the province is expected to be 5 M by Year 5 with the introduction of new ELT and RFA image guided endovascular technologies and existing surgery for varicose veins.
The conclusions on the comparative outcomes between endovascular RFA and surgical ligation and saphenous vein stripping and between endovascular RFA and laser ablation for VV treatment are summarized in the table below (ES Table 1).
Outcome comparisons of RFA vs. surgery and RFA vs ELT for varicose veins
ELT refers to endovascular laser ablation; RFA, radiofrequency ablation
The outcomes of the evidence-based review on these treatments for VV based on different perspectives are summarized below:
RFA First versus Second Generation Catheters and Segmental Ablation
Ablation with second generation catheters and segmental ablation offered technical advantages with improved ease and significant decreases in procedure time. RFA ablation with second generation catheters is also no longer restricted to smaller (< 12 mm diameter) saphenous veins. The safety profile with the new device and method of energy delivery is as good as or improved over the first generation device. No major adverse events were reported in two multicenter prospective cohort studies in 6 month follow-up with over 500 patients. Post-operative complications such as bruising and pain were significantly less with RFA ablation with second generation catheters than ELT in two RCT trials.RFA treatment with second generation catheters has ablation rates that are higher than with first generation catheters and are more comparable with the consistently high rates of ELT.
Endovascular RFA versus Surgery
RFA has a quicker recovery attributable to decreased pain and lower minor complications.RFA, in the short term was comparable to surgery in treatment effectiveness as assessed by imaging defined anatomic outcomes such as vein closure, flow or reflux. Other treatment outcomes such as symptomatic relief and HRQOL were significantly improved in both groups and between group differences in the early peri-operative period were likely influenced by pain experiences. Longer term follow-up was inadequate to evaluate recurrence after either treatment.Patient satisfaction was high after both treatments but was higher for RFA than surgery.
Endovascular RFA versus ELT
RFA has significantly less post-operative pain than ELT but differences were not significant when pain was adjusted for analgesic use and pain differences between groups did not persist at 1 month follow-up.Treatment effectiveness, measured as symptom relief and QOL improvement were similar between the endovascular treatments in the short term (within 1 month) Treatment effectiveness measured as imaging defined vein ablation was not measured in any RCT trials (only for bilateral VV disease) and results were inconsistently reported in observational trials.Longer term follow-up was not available to assess recurrence after either treatment.
System Outcomes – RFA Replacing Surgery or Competing with ELT
RFA may offer system advantages in that the treatment can be offered by several medical specialties in outpatient settings and because it does not require an operating theatre or general anaesthesia. The treatment may result in decanting of patients from OR with decreased pre-surgical investigations, demand on anaesthetists’ time, hospital stay and wait time for VV treatment. It may also provide more reliable outpatient scheduling. Procedure costs may be less for endovascular approaches than surgery but the budget impact may be greater with insurance of RFA because of the transfer of cases from the private market to the public payer system.Competition between RFA and ELT endovascular approaches is likely to continue to stimulate innovation and technical changes to advance patient care and result in competitive pricing.
PMCID: PMC3377553  PMID: 23074413
10.  Course and prognosis of recovery for chronic non-specific low back pain: design, therapy program and baseline data of a prospective cohort study 
There has been increasing focus on factors predicting the development of chronic musculoskeletal disorders. For patients already experiencing chronic non-specific low back pain it is also relevant to investigate which prognostic factors predict recovery. We present the design of a cohort study that aims to determine the course and prognostic factors for recovery in patients with chronic non-specific low back pain.
All participating patients were recruited (Jan 2003-Dec 2008) from the same rehabilitation centre and were evaluated by means of (postal) questionnaires and physical examinations at baseline, during the 2-month therapy program, and at 5 and 12 months after start of therapy. The therapy protocol at the rehabilitation centre used a bio-psychosocial approach to stimulate patients to adopt adequate (movement) behaviour aimed at physical and functional recovery. The program is part of regular care and consists of 16 sessions of 3 hours each, over an 8-week period (in total 48 hours), followed by a 3-month self-management program. The primary outcomes are low back pain intensity, disability, quality of life, patient's global perceived effect of recovery, and participation in work. Baseline characteristics include information on socio-demographics, low back pain, employment status, and additional clinical items status such as fatigue, duration of activities, and fear of kinesiophobia. Prognostic variables are determined for recovery at short-term (5 months) and long-term (12 months) follow-up after start of therapy.
In a routine clinical setting it is important to provide patients suffering from chronic non-specific low back pain with adequate information about the prognosis of their complaint.
PMCID: PMC3221649  PMID: 22047019
11.  On the course of low back pain in general practice: a one year follow up study 
OBJECTIVES—Knowledge on the clinical course of low back pain presented in general practice is poor. Preceding studies offer a fragmentary view only, whereas further knowledge is important to enable the assessment of the prognosis. The object of this study is to investigate the course of low back pain presented in general practice to enable the assessment of the prognosis.
METHODS—A one year follow up study on the clinical course of low back pain in consecutive cases receiving usual care in general practice. During a period of two years 15 general practitioners from Amsterdam and surrounding areas included consecutive patients with both chronic and recent onset low back pain. After the initial visit, each patient was monitored for a period of 12 months. The follow up consisted of monthly postal questionnaires on the course of the low back pain and the related disability.
RESULTS—A total of 443 of 605 patients identified were included in the follow up, which was fully completed by 269 patients. In general, patients with less serious low back pain participated less often or did not complete the follow up. At 12 weeks 35% and at the end of the follow up 10% of the population, respectively, still suffered from low back pain. Both the pain and the disability seemed to diminish quickly after the initial visit, and both seemed to stabilise at a lower level if the low back pain did not disappear completely. About three of four patients, whose pain disappeared before the end of the follow up, endured one or more relapses within a year. The median time to a relapse was about seven weeks, and its median duration about six weeks. Both the pain and the disability turned out to be less severe during relapses. The median time to recovery for patients whose low back pain developed more than seven weeks before the initial visit, was four weeks longer than for patients with more recently developed low back pain at the initial visit.
CONCLUSIONS—The clinical course of low back pain presented in general practice, for the most patients, clearly is less favourable than expected. It takes more than just a few weeks to recover, and relapses occur within a year in most cases. Fortunately, both the pain and the disability quickly diminish, even if the low back pain does not resolve within a few weeks.

 Keywords: backache; prognosis; follow up study; general practice
PMCID: PMC1752458  PMID: 9536816
12.  Retention in physically demanding jobs of individuals with low back pain: study protocol for a randomised controlled trial 
Trials  2015;16:166.
Low back pain is prevalent and is a frequent cause of disability and sick leave among working adults. Individuals with low back pain often consult general practice or other health care providers which often results in a unilateral intervention focussed on their symptoms. Employment is associated with physical and mental well-being, so, patients may benefit from an early additional occupational medicine intervention. For individuals with physically demanding jobs it can be especially challenging to retain their jobs. The aim of the ‘GoBack trial' is to develop and evaluate the efficacy and feasibility of an occupational medicine intervention for individuals with low back pain in physically demanding jobs.
We will conduct a randomised controlled trial enrolling 300 participants with difficulty in maintaining physically demanding jobs due to low back pain for a current period of 2 to 4 weeks. Participants will be randomised and stratified according to their age and gender before being allocated in a 1:1 ratio to either control or additional occupational medicine intervention. Both groups will receive conventional treatment for their low back pain during the study. All participants will be thoroughly assessed for causes of low back pain and potential prognostic factors by questionnaires, clinical specialist assessments and magnetic resonance imaging (MRI) scans of the lumbar spine. Primary outcome is the accumulated duration of self-assessed sick leave (in days) due to low back pain during 6 months from baseline. Secondary outcomes include general self-rated back pain, disability and screening for potential prognostic factors: fear avoidance behaviour, disability, health status and degenerative MRI findings. For tertiary purposes selected outcomes will also be assessed after 1 and 2 years from baseline.
Many guidelines exist for the management of low back pain, but they provide limited guidance on occupational aspects. The findings from this randomised trial will provide high-quality evidence for the efficacy and feasibility of an occupational medicine intervention model for individuals with low back pain in physically demanding jobs.
Trial registration
This trial was registered with (identifier: NCT02015572) on 29 November 2013.
PMCID: PMC4423126  PMID: 25887302
Low back pain; Sick leave; Workplace intervention; MRI; Weight-bearing; Occupational medicine; Physically demanding jobs; G-MRI
13.  Predicting persistent disabling low back pain in general practice: a prospective cohort study 
Patients may adopt active and/or passive coping strategies in response to pain. However, it is not known whether these strategies may also precede the onset of chronic symptoms and, if so, whether they are independent predictors of prognosis.
To examine, in patients with low back pain in general practice, the prognostic value of active and passive coping styles, in the context of baseline levels of pain, disability and pain duration.
Design of study
Prospective cohort study.
Nine general practices in north west England.
Patients consulting their GP with a new episode of low back pain were recruited to the study. Information on coping styles, pain severity, disability, duration, and a brief history of other chronic pain symptoms was recorded using a self-completion postal questionnaire. Participants were then sent a follow-up questionnaire, 3 months after their initial consultation, to assess the occurrence of low back pain. The primary outcome was persistent disabling low back pain, that is, low back pain at 3-month follow-up self-rated as ≥20 mm on a 100 mm visual analogue scale, and ≥5 on the Roland and Morris Disability Questionnaire.
A total of 974 patients took part in the baseline survey, of whom 922 (95%) completed a follow-up questionnaire; 363 individuals (39%) reported persistent disabling pain at follow-up. Persons who reported high levels of passive coping experienced a threefold increase in the risk of persistent disabling low back pain (relative risk [RR] = 3.0; 95% confidence interval [CI] = 2.3 to 4.0). In contrast, active coping was associated with neither an increase nor a decrease in the risk of a poor prognosis. After adjusting for baseline pain severity, disability, and other measures of pain and pain history, persons who reported a high passive coping score were still at 50% increased risk of a poor outcome (RR = 1.5; 95% CI = 1.1 to 2.0).
Patients who report passive coping strategies experience a significant increase in the risk of persistent symptoms. Further, this risk persists after controlling for initial pain severity and disability. The identification of this low back pain subgroup may help target future treatments to those at greatest risk of a poor outcome.
PMCID: PMC1837841  PMID: 16638248
coping behavior; general practice; low back pain; prognosis
14.  Acupuncture for acute non-specific low back pain: a protocol for a randomised, controlled multicentre intervention study in general practice—the Acuback Study 
BMJ Open  2012;2(3):e001164.
Some general practitioners (GPs) treat acute low back pain (LBP) with acupuncture, despite lacking evidence of its effectiveness for this condition. The aim of this study was to evaluate whether a single treatment session with acupuncture can reduce time to recovery when applied in addition to standard LBP treatment according to the Norwegian national guidelines. Analyses of prognostic factors for recovery and cost-effectiveness will also be carried out.
Methods and analysis
In this randomised, controlled multicentre study in general practice in Southern Norway, 270 patients will be allocated into one of two treatment groups, using a web-based application based on block randomisation. Outcome assessor will be blinded for group allocation of the patients. The control group will receive standard treatment, while the intervention group will receive standard treatment plus acupuncture treatment. There will be different GPs treating the two groups, and both groups will just have one consultation. Adults who consult their GP because of acute LBP will be included. Patients with nerve root affection, ‘red flags’, pregnancy, previous sick leave more than 14 days and disability pension will be excluded. The primary outcome of the study is the median time to recovery (in days). The secondary outcomes are rated global improvement, back-specific functional status, sick leave, medication, GP visits and side effects. A pilot study will be conducted.
Ethics and dissemination
Participation is based on informed written consent. The authors will apply for an ethical approval from the Regional Committee for Medical and Health Research Ethics when the study protocol is published. Results from this study, positive or negative, will be disseminated in scientific medical journals.
Trial Registration Number Identifier: NCT01439412.
Article summary
Article focus
Does acupuncture treatment contribute to faster pain recovery in acute LBP compared with standard treatment in general practice provided in accordance with the Norwegian national guidelines?
Does acupuncture treatment for acute LBP improve function and reduce drug use and sick leave?
Is acupuncture treatment for acute LBP a cost-effective treatment in general practice?
Key messages
This project will increase the knowledge about the effects of acupuncture treatment for acute LBP.
The primary outcome is the median time in days for recovery from pain.
A faster pain relief will aid the patients to earlier return to normal, everyday activities, including return to their work.
Strengths and limitations of this study
The methodology of the trial is stronger than previous studies.
There are still methodological challenges in acupuncture trials; in this trial, neither the patient or the GP will be blinded, and the consultation time will be longer in the intervention group.
PMCID: PMC3383982  PMID: 22734119
15.  Psychosocial factors and their predictive value in chiropractic patients with low back pain: a prospective inception cohort study 
Being able to estimate the likelihood of poor recovery from episodes of back pain is important for care. Studies of psychosocial factors in inception cohorts in general practice and occupational populations have begun to make inroads to these problems. However, no studies have yet investigated this in chiropractic patients.
A prospective inception cohort study of patients presenting to a UK chiropractic practice for new episodes of non-specific low back pain (LBP) was conducted. Baseline questionnaires asked about age, gender, occupation, work status, duration of current episode, chronicity, aggravating features and bothersomeness using Deyo's 'Core Set'. Psychological factors (fear-avoidance beliefs, inevitability, anxiety/distress and coping, and co-morbidity were also assessed at baseline. Satisfaction with care, number of attendances and pain impact were determined at 6 weeks. Predictors of poor outcome were sought by the calculation of relative risk ratios.
Most patients presented within 4 weeks of onset. Of 158 eligible and willing patients, 130 completed both baseline and 6-week follow-up questionnaires. Greatest improvements at 6 weeks were in interference with normal work (ES 1.12) and LBP bothersomeness (ES 1.37). Although most patients began with moderate-high back pain bothersomeness scores, few had high psychometric ones. Co-morbidity was a risk for high-moderate interference with normal work at 6 weeks (RR 2.37; 95% C.I. 1.15–4.74). An episode duration of >4 weeks was associated with moderate to high bothersomeness at 6 weeks (RR 2.07; 95% C.I. 1.19 – 3.38) and negative outlook (inevitability) with moderate to high interference with normal work (RR 2.56; 95% C.I. 1.08 – 5.08).
Patients attending a private UK chiropractic clinic for new episodes of non-specific LBP exhibited few psychosocial predictors of poor outcome, unlike other patient populations that have been studied. Despite considerable bothersomeness at baseline, scores were low at follow-up. In this independent health sector back pain population, general health and duration of episode before consulting appeared more important to outcome than psychosocial factors.
PMCID: PMC1852566  PMID: 17394652
16.  Study protocol of effectiveness of a biopsychosocial multidisciplinary intervention in the evolution of non-speficic sub-acute low back pain in the working population: cluster randomised trial 
Non-specific low back pain is a common cause for consultation with the general practitioner, generating increased health and social costs. This study will analyse the effectiveness of a multidisciplinary intervention to reduce disability, severity of pain, anxiety and depression, to improve quality of life and to reduce the incidence of chronic low back pain in the working population with non-specific low back pain, compared to usual clinical care.
A Cluster randomised clinical trial will be conducted in 38 Primary Health Care Centres located in Barcelona, Spain and its surrounding areas. The centres are randomly allocated to the multidisciplinary intervention or to usual clinical care. Patients between 18 and 65 years old (n = 932; 466 per arm) and with a diagnostic of a non-specific sub-acute low back pain are included. Patients in the intervention group are receiving the recommendations of clinical practice guidelines, in addition to a biopsychosocial multidisciplinary intervention consisting of group educational sessions lasting a total of 10 hours. The main outcome is change in the score in the Roland Morris disability questionnaire at three months after onset of pain. Other outcomes are severity of pain, quality of life, duration of current non-specific low back pain episode, work sick leave and duration, Fear Avoidance Beliefs and Goldberg Questionnaires. Outcomes will be assessed at baseline, 3, 6 and 12 months. Analysis will be by intention to treat. The intervention effect will be assessed through the standard error of measurement and the effect-size. Responsiveness of each scale will be evaluated by standardised response mean and receiver-operating characteristic method. Recovery according to the patient will be used as an external criterion. A multilevel regression will be performed on repeated measures. The time until the current episode of low back pain takes to subside will be analysed by Cox regression.
We hope to provide evidence of the effectiveness of the proposed biopsychosocial multidisciplinary intervention in avoiding the chronification of low back pain, and to reduce the duration of non-specific low back pain episodes. If the intervention is effective, it could be applied to Primary Health Care Centres.
Trial Registration
PMCID: PMC2820035  PMID: 20067619
17.  Randomised controlled trial of integrated care to reduce disability from chronic low back pain in working and private life 
Objective To evaluate the effectiveness of an integrated care programme, combining a patient directed and a workplace directed intervention, for patients with chronic low back pain.
Design Population based randomised controlled trial.
Setting Primary care (10 physiotherapy practices, one occupational health service, one occupational therapy practice) and secondary care (five hospitals).
Participants 134 adults aged 18-65 sick listed for at least 12 weeks owing to low back pain.
Intervention Patients were randomly assigned to usual care (n=68) or integrated care (n=66). Integrated care consisted of a workplace intervention based on participatory ergonomics, involving a supervisor, and a graded activity programme based on cognitive behavioural principles.
Main outcome measures The primary outcome was the duration of time off work (work disability) due to low back pain until full sustainable return to work. Secondary outcome measures were intensity of pain and functional status.
Results The median duration until sustainable return to work was 88 days in the integrated care group compared with 208 days in the usual care group (P=0.003). Integrated care was effective on return to work (hazard ratio 1.9, 95% confidence interval 1.2 to 2.8, P=0.004). After 12 months, patients in the integrated care group improved significantly more on functional status compared with patients in the usual care group (P=0.01). Improvement of pain between the groups did not differ significantly.
Conclusion The integrated care programme substantially reduced disability due to chronic low back pain in private and working life.
Trial registration Current Controlled Trials ISRCTN28478651.
PMCID: PMC2840223  PMID: 20234040
18.  Prognosis of patients with whiplash-associated disorders consulting physiotherapy: development of a predictive model for recovery 
Patients with whiplash-associated disorders (WAD) have a generally favourable prognosis, yet some develop longstanding pain and disability. Predicting who will recover from WAD shortly after a traffic collision is very challenging for health care providers such as physical therapists. Therefore, we aimed to develop a prediction model for the recovery of WAD in a cohort of patients who consulted physical therapists within six weeks after the injury.
Our cohort included 680 adult patients with WAD who were injured in Saskatchewan, Canada, between 1997 and 1999. All patients had consulted a physical therapist as a result of the injury. Baseline prognostic factors were collected from an injury questionnaire administered by Saskatchewan Government Insurance. The outcome, global self-perceived recovery, was assessed by telephone interviews six weeks, three and six months later. Twenty-five possible baseline prognostic factors were considered in the analyses. A prediction model was built using Cox regression. The predictive ability of the model was estimated with concordance statistics (c-index). Internal validity was checked using bootstrapping.
Our final prediction model included: age, number of days to reporting the collision, neck pain intensity, low back pain intensity, pain other than neck and back pain, headache before collision and recovery expectations. The model had an acceptable level of predictive ability with a c-index of 0.68 (95% CI: 0.65, 0.71). Internal validation showed that our model was robust and had a good fit.
We developed a model predicting recovery from WAD, in a cohort of patients who consulted physical therapists. Our model has adequate predictive ability. However, to be fully incorporated in clinical practice the model needs to be validated in other populations and tested in clinical settings.
PMCID: PMC3544579  PMID: 23273330
Prediction; Prognosis; Whiplash-associated disorders; Neck pain; Physical therapy; Cohort; Recovery; Regression; Discrimination
19.  Patterns and Determinants of Multiple Provider Use in Patients with Acute Low Back Pain 
To describe the patterns of provider use associated with an acute episode of nonspecific low back pain and their impact on cost.
The analysis is based on a prospective cohort study of patients with acute low back pain followed until they recovered completely or to 6 months. Patients were followed after an initial visit to one of four provider types: private primary care physician, chiropractor, orthopedic surgeon, or HMO primary care physician. Follow-up interviews were conducted at baseline, 2, 4, 8, 12, and 24 weeks; 1,580 (97%) of the participants completed the 6-month follow-up.
Seventy-nine percent of patients saw only the initial provider who began their care for low back pain. Logistic regression revealed that duration of pain prior to initial visit, sciatica, higher Roland disability score, days to functional recovery, interval to complete recovery, referral by initial provider, disk attribution, satisfaction, and the type of index provider were significantly (p < .05) associated with seeking care from multiple provider types. Age, race, gender, and education were not significant. The adjusted proportions of multiple provider type use were 14% (95% confidence interval [CI] 11%, 17%) for the private primary care provider stratum; 19% (95% CI 16%, 23%) for the chiropractic stratum; 30% (95% CI 23%, 37%) for the orthopedic stratum; and 9% (95% CI 5%, 14%) for the HMO primary care physician stratum. Cost of seeing only the index provider was $439 (95% CI $404, $475), and cost of seeing multiple provider types was $1,137 (95% CI $1,064, $1,211) based on the adjusted model.
Use of multiple provider types, is associated with several factors, one of which is the initial provider type. The cost of such use is significant.
PMCID: PMC1497001  PMID: 9734789
low back pain; health care utilization; cost; disability; chiropractors
20.  Clinical course, characteristics and prognostic indicators in patients presenting with back and leg pain in primary care. The ATLAS study protocol 
Low-back related leg pain with or without nerve root involvement is associated with a poor prognosis compared to low back pain (LBP) alone. Compared to the literature investigating prognostic indicators of outcome for LBP, there is limited evidence on prognostic factors for low back-related leg pain including the group with nerve root pain. This 1 year prospective consultation-based observational cohort study will describe the clinical, imaging, demographic characteristics and health economic outcomes for the whole cohort, will investigate differences and identify prognostic indicators of outcome (i.e. change in disability at 12 months), for the whole cohort and, separately, for those classified with and without nerve root pain. In addition, nested qualitative studies will provide insights on the clinical consultation and the impact of diagnosis and treatment on patients' symptom management and illness trajectory.
Adults aged 18 years and over consulting their General Practitioner (GP) with LBP and radiating leg pain of any duration at (n = 500) GP practices in North Staffordshire and Stoke-on-Trent, UK will be invited to participate. All participants will receive a standardised assessment at the clinic by a study physiotherapist and will be classified according to the clinically determined presence or absence of nerve root pain/involvement. All will undergo a lumbar spine MRI scan. All participants will be managed according to their clinical need. The study outcomes will be measured at 4 and 12 months using postal self-complete questionnaires. Data will also be collected each month using brief postal questionnaires to enable detailed description of the course of low back and leg pain over time. Clinical observations and patient interviews will be used for the qualitative aspects of the study.
This prospective clinical observational cohort will combine self-reported data, comprehensive clinical and MRI assessment, together with qualitative enquiries, to describe the course, health care usage, patients' experiences and prognostic indicators in an adult population presenting in primary care with LBP and leg pain with or without nerve root involvement.
PMCID: PMC3293000  PMID: 22264273
21.  Internet-Based Device-Assisted Remote Monitoring of Cardiovascular Implantable Electronic Devices 
Executive Summary
The objective of this Medical Advisory Secretariat (MAS) report was to conduct a systematic review of the available published evidence on the safety, effectiveness, and cost-effectiveness of Internet-based device-assisted remote monitoring systems (RMSs) for therapeutic cardiac implantable electronic devices (CIEDs) such as pacemakers (PMs), implantable cardioverter-defibrillators (ICDs), and cardiac resynchronization therapy (CRT) devices. The MAS evidence-based review was performed to support public financing decisions.
Clinical Need: Condition and Target Population
Sudden cardiac death (SCD) is a major cause of fatalities in developed countries. In the United States almost half a million people die of SCD annually, resulting in more deaths than stroke, lung cancer, breast cancer, and AIDS combined. In Canada each year more than 40,000 people die from a cardiovascular related cause; approximately half of these deaths are attributable to SCD.
Most cases of SCD occur in the general population typically in those without a known history of heart disease. Most SCDs are caused by cardiac arrhythmia, an abnormal heart rhythm caused by malfunctions of the heart’s electrical system. Up to half of patients with significant heart failure (HF) also have advanced conduction abnormalities.
Cardiac arrhythmias are managed by a variety of drugs, ablative procedures, and therapeutic CIEDs. The range of CIEDs includes pacemakers (PMs), implantable cardioverter-defibrillators (ICDs), and cardiac resynchronization therapy (CRT) devices. Bradycardia is the main indication for PMs and individuals at high risk for SCD are often treated by ICDs.
Heart failure (HF) is also a significant health problem and is the most frequent cause of hospitalization in those over 65 years of age. Patients with moderate to severe HF may also have cardiac arrhythmias, although the cause may be related more to heart pump or haemodynamic failure. The presence of HF, however, increases the risk of SCD five-fold, regardless of aetiology. Patients with HF who remain highly symptomatic despite optimal drug therapy are sometimes also treated with CRT devices.
With an increasing prevalence of age-related conditions such as chronic HF and the expanding indications for ICD therapy, the rate of ICD placement has been dramatically increasing. The appropriate indications for ICD placement, as well as the rate of ICD placement, are increasingly an issue. In the United States, after the introduction of expanded coverage of ICDs, a national ICD registry was created in 2005 to track these devices. A recent survey based on this national ICD registry reported that 22.5% (25,145) of patients had received a non-evidence based ICD and that these patients experienced significantly higher in-hospital mortality and post-procedural complications.
In addition to the increased ICD device placement and the upfront device costs, there is the need for lifelong follow-up or surveillance, placing a significant burden on patients and device clinics. In 2007, over 1.6 million CIEDs were implanted in Europe and the United States, which translates to over 5.5 million patient encounters per year if the recommended follow-up practices are considered. A safe and effective RMS could potentially improve the efficiency of long-term follow-up of patients and their CIEDs.
In addition to being therapeutic devices, CIEDs have extensive diagnostic abilities. All CIEDs can be interrogated and reprogrammed during an in-clinic visit using an inductive programming wand. Remote monitoring would allow patients to transmit information recorded in their devices from the comfort of their own homes. Currently most ICD devices also have the potential to be remotely monitored. Remote monitoring (RM) can be used to check system integrity, to alert on arrhythmic episodes, and to potentially replace in-clinic follow-ups and manage disease remotely. They do not currently have the capability of being reprogrammed remotely, although this feature is being tested in pilot settings.
Every RMS is specifically designed by a manufacturer for their cardiac implant devices. For Internet-based device-assisted RMSs, this customization includes details such as web application, multiplatform sensors, custom algorithms, programming information, and types and methods of alerting patients and/or physicians. The addition of peripherals for monitoring weight and pressure or communicating with patients through the onsite communicators also varies by manufacturer. Internet-based device-assisted RMSs for CIEDs are intended to function as a surveillance system rather than an emergency system.
Health care providers therefore need to learn each application, and as more than one application may be used at one site, multiple applications may need to be reviewed for alarms. All RMSs deliver system integrity alerting; however, some systems seem to be better geared to fast arrhythmic alerting, whereas other systems appear to be more intended for remote follow-up or supplemental remote disease management. The different RMSs may therefore have different impacts on workflow organization because of their varying frequency of interrogation and methods of alerts. The integration of these proprietary RM web-based registry systems with hospital-based electronic health record systems has so far not been commonly implemented.
Currently there are 2 general types of RMSs: those that transmit device diagnostic information automatically and without patient assistance to secure Internet-based registry systems, and those that require patient assistance to transmit information. Both systems employ the use of preprogrammed alerts that are either transmitted automatically or at regular scheduled intervals to patients and/or physicians.
The current web applications, programming, and registry systems differ greatly between the manufacturers of transmitting cardiac devices. In Canada there are currently 4 manufacturers—Medtronic Inc., Biotronik, Boston Scientific Corp., and St Jude Medical Inc.—which have regulatory approval for remote transmitting CIEDs. Remote monitoring systems are proprietary to the manufacturer of the implant device. An RMS for one device will not work with another device, and the RMS may not work with all versions of the manufacturer’s devices.
All Internet-based device-assisted RMSs have common components. The implanted device is equipped with a micro-antenna that communicates with a small external device (at bedside or wearable) commonly known as the transmitter. Transmitters are able to interrogate programmed parameters and diagnostic data stored in the patients’ implant device. The information transfer to the communicator can occur at preset time intervals with the participation of the patient (waving a wand over the device) or it can be sent automatically (wirelessly) without their participation. The encrypted data are then uploaded to an Internet-based database on a secure central server. The data processing facilities at the central database, depending on the clinical urgency, can trigger an alert for the physician(s) that can be sent via email, fax, text message, or phone. The details are also posted on the secure website for viewing by the physician (or their delegate) at their convenience.
Research Questions
The research directions and specific research questions for this evidence review were as follows:
To identify the Internet-based device-assisted RMSs available for follow-up of patients with therapeutic CIEDs such as PMs, ICDs, and CRT devices.
To identify the potential risks, operational issues, or organizational issues related to Internet-based device-assisted RM for CIEDs.
To evaluate the safety, acceptability, and effectiveness of Internet-based device-assisted RMSs for CIEDs such as PMs, ICDs, and CRT devices.
To evaluate the safety, effectiveness, and cost-effectiveness of Internet-based device-assisted RMSs for CIEDs compared to usual outpatient in-office monitoring strategies.
To evaluate the resource implications or budget impact of RMSs for CIEDs in Ontario, Canada.
Research Methods
Literature Search
The review included a systematic review of published scientific literature and consultations with experts and manufacturers of all 4 approved RMSs for CIEDs in Canada. Information on CIED cardiac implant clinics was also obtained from Provincial Programs, a division within the Ministry of Health and Long-Term Care with a mandate for cardiac implant specialty care. Various administrative databases and registries were used to outline the current clinical follow-up burden of CIEDs in Ontario. The provincial population-based ICD database developed and maintained by the Institute for Clinical Evaluative Sciences (ICES) was used to review the current follow-up practices with Ontario patients implanted with ICD devices.
Search Strategy
A literature search was performed on September 21, 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 1950 to September 2010. Search alerts were generated and reviewed for additional relevant literature until December 31, 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.
Inclusion Criteria
published between 1950 and September 2010;
English language full-reports and human studies;
original reports including clinical evaluations of Internet-based device-assisted RMSs for CIEDs in clinical settings;
reports including standardized measurements on outcome events such as technical success, safety, effectiveness, cost, measures of health care utilization, morbidity, mortality, quality of life or patient satisfaction;
randomized controlled trials (RCTs), systematic reviews and meta-analyses, cohort and controlled clinical studies.
Exclusion Criteria
non-systematic reviews, letters, comments and editorials;
reports not involving standardized outcome events;
clinical reports not involving Internet-based device assisted RM systems for CIEDs in clinical settings;
reports involving studies testing or validating algorithms without RM;
studies with small samples (<10 subjects).
Outcomes of Interest
The outcomes of interest included: technical outcomes, emergency department visits, complications, major adverse events, symptoms, hospital admissions, clinic visits (scheduled and/or unscheduled), survival, morbidity (disease progression, stroke, etc.), patient satisfaction, and quality of life.
Summary of Findings
The MAS evidence review was performed to review available evidence on Internet-based device-assisted RMSs for CIEDs published until September 2010. The search identified 6 systematic reviews, 7 randomized controlled trials, and 19 reports for 16 cohort studies—3 of these being registry-based and 4 being multi-centered. The evidence is summarized in the 3 sections that follow.
1. Effectiveness of Remote Monitoring Systems of CIEDs for Cardiac Arrhythmia and Device Functioning
In total, 15 reports on 13 cohort studies involving investigations with 4 different RMSs for CIEDs in cardiology implant clinic groups were identified in the review. The 4 RMSs were: Care Link Network® (Medtronic Inc,, Minneapolis, MN, USA); Home Monitoring® (Biotronic, Berlin, Germany); House Call 11® (St Jude Medical Inc., St Pauls, MN, USA); and a manufacturer-independent RMS. Eight of these reports were with the Home Monitoring® RMS (12,949 patients), 3 were with the Care Link® RMS (167 patients), 1 was with the House Call 11® RMS (124 patients), and 1 was with a manufacturer-independent RMS (44 patients). All of the studies, except for 2 in the United States, (1 with Home Monitoring® and 1 with House Call 11®), were performed in European countries.
The RMSs in the studies were evaluated with different cardiac implant device populations: ICDs only (6 studies), ICD and CRT devices (3 studies), PM and ICD and CRT devices (4 studies), and PMs only (2 studies). The patient populations were predominately male (range, 52%–87%) in all studies, with mean ages ranging from 58 to 76 years. One study population was unique in that RMSs were evaluated for ICDs implanted solely for primary prevention in young patients (mean age, 44 years) with Brugada syndrome, which carries an inherited increased genetic risk for sudden heart attack in young adults.
Most of the cohort studies reported on the feasibility of RMSs in clinical settings with limited follow-up. In the short follow-up periods of the studies, the majority of the events were related to detection of medical events rather than system configuration or device abnormalities. The results of the studies are summarized below:
The interrogation of devices on the web platform, both for continuous and scheduled transmissions, was significantly quicker with remote follow-up, both for nurses and physicians.
In a case-control study focusing on a Brugada population–based registry with patients followed-up remotely, there were significantly fewer outpatient visits and greater detection of inappropriate shocks. One death occurred in the control group not followed remotely and post-mortem analysis indicated early signs of lead failure prior to the event.
Two studies examined the role of RMSs in following ICD leads under regulatory advisory in a European clinical setting and noted:
– Fewer inappropriate shocks were administered in the RM group.
– Urgent in-office interrogations and surgical revisions were performed within 12 days of remote alerts.
– No signs of lead fracture were detected at in-office follow-up; all were detected at remote follow-up.
Only 1 study reported evaluating quality of life in patients followed up remotely at 3 and 6 months; no values were reported.
Patient satisfaction was evaluated in 5 cohort studies, all in short term follow-up: 1 for the Home Monitoring® RMS, 3 for the Care Link® RMS, and 1 for the House Call 11® RMS.
– Patients reported receiving a sense of security from the transmitter, a good relationship with nurses and physicians, positive implications for their health, and satisfaction with RM and organization of services.
– Although patients reported that the system was easy to implement and required less than 10 minutes to transmit information, a variable proportion of patients (range, 9% 39%) reported that they needed the assistance of a caregiver for their transmission.
– The majority of patients would recommend RM to other ICD patients.
– Patients with hearing or other physical or mental conditions hindering the use of the system were excluded from studies, but the frequency of this was not reported.
Physician satisfaction was evaluated in 3 studies, all with the Care Link® RMS:
– Physicians reported an ease of use and high satisfaction with a generally short-term use of the RMS.
– Physicians reported being able to address the problems in unscheduled patient transmissions or physician initiated transmissions remotely, and were able to handle the majority of the troubleshooting calls remotely.
– Both nurses and physicians reported a high level of satisfaction with the web registry system.
2. Effectiveness of Remote Monitoring Systems in Heart Failure Patients for Cardiac Arrhythmia and Heart Failure Episodes
Remote follow-up of HF patients implanted with ICD or CRT devices, generally managed in specialized HF clinics, was evaluated in 3 cohort studies: 1 involved the Home Monitoring® RMS and 2 involved the Care Link® RMS. In these RMSs, in addition to the standard diagnostic features, the cardiac devices continuously assess other variables such as patient activity, mean heart rate, and heart rate variability. Intra-thoracic impedance, a proxy measure for lung fluid overload, was also measured in the Care Link® studies. The overall diagnostic performance of these measures cannot be evaluated, as the information was not reported for patients who did not experience intra-thoracic impedance threshold crossings or did not undergo interventions. The trial results involved descriptive information on transmissions and alerts in patients experiencing high morbidity and hospitalization in the short study periods.
3. Comparative Effectiveness of Remote Monitoring Systems for CIEDs
Seven RCTs were identified evaluating RMSs for CIEDs: 2 were for PMs (1276 patients) and 5 were for ICD/CRT devices (3733 patients). Studies performed in the clinical setting in the United States involved both the Care Link® RMS and the Home Monitoring® RMS, whereas all studies performed in European countries involved only the Home Monitoring® RMS.
3A. Randomized Controlled Trials of Remote Monitoring Systems for Pacemakers
Two trials, both multicenter RCTs, were conducted in different countries with different RMSs and study objectives. The PREFER trial was a large trial (897 patients) performed in the United States examining the ability of Care Link®, an Internet-based remote PM interrogation system, to detect clinically actionable events (CAEs) sooner than the current in-office follow-up supplemented with transtelephonic monitoring transmissions, a limited form of remote device interrogation. The trial results are summarized below:
In the 375-day mean follow-up, 382 patients were identified with at least 1 CAE—111 patients in the control arm and 271 in the remote arm.
The event rate detected per patient for every type of CAE, except for loss of atrial capture, was higher in the remote arm than the control arm.
The median time to first detection of CAEs (4.9 vs. 6.3 months) was significantly shorter in the RMS group compared to the control group (P < 0.0001).
Additionally, only 2% (3/190) of the CAEs in the control arm were detected during a transtelephonic monitoring transmission (the rest were detected at in-office follow-ups), whereas 66% (446/676) of the CAEs were detected during remote interrogation.
The second study, the OEDIPE trial, was a smaller trial (379 patients) performed in France evaluating the ability of the Home Monitoring® RMS to shorten PM post-operative hospitalization while preserving the safety of conventional management of longer hospital stays.
Implementation and operationalization of the RMS was reported to be successful in 91% (346/379) of the patients and represented 8144 transmissions.
In the RM group 6.5% of patients failed to send messages (10 due to improper use of the transmitter, 2 with unmanageable stress). Of the 172 patients transmitting, 108 patients sent a total of 167 warnings during the trial, with a greater proportion of warnings being attributed to medical rather than technical causes.
Forty percent had no warning message transmission and among these, 6 patients experienced a major adverse event and 1 patient experienced a non-major adverse event. Of the 6 patients having a major adverse event, 5 contacted their physician.
The mean medical reaction time was faster in the RM group (6.5 ± 7.6 days vs. 11.4 ± 11.6 days).
The mean duration of hospitalization was significantly shorter (P < 0.001) for the RM group than the control group (3.2 ± 3.2 days vs. 4.8 ± 3.7 days).
Quality of life estimates by the SF-36 questionnaire were similar for the 2 groups at 1-month follow-up.
3B. Randomized Controlled Trials Evaluating Remote Monitoring Systems for ICD or CRT Devices
The 5 studies evaluating the impact of RMSs with ICD/CRT devices were conducted in the United States and in European countries and involved 2 RMSs—Care Link® and Home Monitoring ®. The objectives of the trials varied and 3 of the trials were smaller pilot investigations.
The first of the smaller studies (151 patients) evaluated patient satisfaction, achievement of patient outcomes, and the cost-effectiveness of the Care Link® RMS compared to quarterly in-office device interrogations with 1-year follow-up.
Individual outcomes such as hospitalizations, emergency department visits, and unscheduled clinic visits were not significantly different between the study groups.
Except for a significantly higher detection of atrial fibrillation in the RM group, data on ICD detection and therapy were similar in the study groups.
Health-related quality of life evaluated by the EuroQoL at 6-month or 12-month follow-up was not different between study groups.
Patients were more satisfied with their ICD care in the clinic follow-up group than in the remote follow-up group at 6-month follow-up, but were equally satisfied at 12- month follow-up.
The second small pilot trial (20 patients) examined the impact of RM follow-up with the House Call 11® system on work schedules and cost savings in patients randomized to 2 study arms varying in the degree of remote follow-up.
The total time including device interrogation, transmission time, data analysis, and physician time required was significantly shorter for the RM follow-up group.
The in-clinic waiting time was eliminated for patients in the RM follow-up group.
The physician talk time was significantly reduced in the RM follow-up group (P < 0.05).
The time for the actual device interrogation did not differ in the study groups.
The third small trial (115 patients) examined the impact of RM with the Home Monitoring® system compared to scheduled trimonthly in-clinic visits on the number of unplanned visits, total costs, health-related quality of life (SF-36), and overall mortality.
There was a 63.2% reduction in in-office visits in the RM group.
Hospitalizations or overall mortality (values not stated) were not significantly different between the study groups.
Patient-induced visits were higher in the RM group than the in-clinic follow-up group.
The TRUST Trial
The TRUST trial was a large multicenter RCT conducted at 102 centers in the United States involving the Home Monitoring® RMS for ICD devices for 1450 patients. The primary objectives of the trial were to determine if remote follow-up could be safely substituted for in-office clinic follow-up (3 in-office visits replaced) and still enable earlier physician detection of clinically actionable events.
Adherence to the protocol follow-up schedule was significantly higher in the RM group than the in-office follow-up group (93.5% vs. 88.7%, P < 0.001).
Actionability of trimonthly scheduled checks was low (6.6%) in both study groups. Overall, actionable causes were reprogramming (76.2%), medication changes (24.8%), and lead/system revisions (4%), and these were not different between the 2 study groups.
The overall mean number of in-clinic and hospital visits was significantly lower in the RM group than the in-office follow-up group (2.1 per patient-year vs. 3.8 per patient-year, P < 0.001), representing a 45% visit reduction at 12 months.
The median time from onset of first arrhythmia to physician evaluation was significantly shorter (P < 0.001) in the RM group than in the in-office follow-up group for all arrhythmias (1 day vs. 35.5 days).
The median time to detect clinically asymptomatic arrhythmia events—atrial fibrillation (AF), ventricular fibrillation (VF), ventricular tachycardia (VT), and supra-ventricular tachycardia (SVT)—was also significantly shorter (P < 0.001) in the RM group compared to the in-office follow-up group (1 day vs. 41.5 days) and was significantly quicker for each of the clinical arrhythmia events—AF (5.5 days vs. 40 days), VT (1 day vs. 28 days), VF (1 day vs. 36 days), and SVT (2 days vs. 39 days).
System-related problems occurred infrequently in both groups—in 1.5% of patients (14/908) in the RM group and in 0.7% of patients (3/432) in the in-office follow-up group.
The overall adverse event rate over 12 months was not significantly different between the 2 groups and individual adverse events were also not significantly different between the RM group and the in-office follow-up group: death (3.4% vs. 4.9%), stroke (0.3% vs. 1.2%), and surgical intervention (6.6% vs. 4.9%), respectively.
The 12-month cumulative survival was 96.4% (95% confidence interval [CI], 95.5%–97.6%) in the RM group and 94.2% (95% confidence interval [CI], 91.8%–96.6%) in the in-office follow-up group, and was not significantly different between the 2 groups (P = 0.174).
The CONNECT trial, another major multicenter RCT, involved the Care Link® RMS for ICD/CRT devices in a15-month follow-up study of 1,997 patients at 133 sites in the United States. The primary objective of the trial was to determine whether automatically transmitted physician alerts decreased the time from the occurrence of clinically relevant events to medical decisions. The trial results are summarized below:
Of the 575 clinical alerts sent in the study, 246 did not trigger an automatic physician alert. Transmission failures were related to technical issues such as the alert not being programmed or not being reset, and/or a variety of patient factors such as not being at home and the monitor not being plugged in or set up.
The overall mean time from the clinically relevant event to the clinical decision was significantly shorter (P < 0.001) by 17.4 days in the remote follow-up group (4.6 days for 172 patients) than the in-office follow-up group (22 days for 145 patients).
– The median time to a clinical decision was shorter in the remote follow-up group than in the in-office follow-up group for an AT/AF burden greater than or equal to 12 hours (3 days vs. 24 days) and a fast VF rate greater than or equal to 120 beats per minute (4 days vs. 23 days).
Although infrequent, similar low numbers of events involving low battery and VF detection/therapy turned off were noted in both groups. More alerts, however, were noted for out-of-range lead impedance in the RM group (18 vs. 6 patients), and the time to detect these critical events was significantly shorter in the RM group (same day vs. 17 days).
Total in-office clinic visits were reduced by 38% from 6.27 visits per patient-year in the in-office follow-up group to 3.29 visits per patient-year in the remote follow-up group.
Health care utilization visits (N = 6,227) that included cardiovascular-related hospitalization, emergency department visits, and unscheduled clinic visits were not significantly higher in the remote follow-up group.
The overall mean length of hospitalization was significantly shorter (P = 0.002) for those in the remote follow-up group (3.3 days vs. 4.0 days) and was shorter both for patients with ICD (3.0 days vs. 3.6 days) and CRT (3.8 days vs. 4.7 days) implants.
The mortality rate between the study arms was not significantly different between the follow-up groups for the ICDs (P = 0.31) or the CRT devices with defribillator (P = 0.46).
There is limited clinical trial information on the effectiveness of RMSs for PMs. However, for RMSs for ICD devices, multiple cohort studies and 2 large multicenter RCTs demonstrated feasibility and significant reductions in in-office clinic follow-ups with RMSs in the first year post implantation. The detection rates of clinically significant events (and asymptomatic events) were higher, and the time to a clinical decision for these events was significantly shorter, in the remote follow-up groups than in the in-office follow-up groups. The earlier detection of clinical events in the remote follow-up groups, however, was not associated with lower morbidity or mortality rates in the 1-year follow-up. The substitution of almost all the first year in-office clinic follow-ups with RM was also not associated with an increased health care utilization such as emergency department visits or hospitalizations.
The follow-up in the trials was generally short-term, up to 1 year, and was a more limited assessment of potential longer term device/lead integrity complications or issues. None of the studies compared the different RMSs, particularly the different RMSs involving patient-scheduled transmissions or automatic transmissions. Patients’ acceptance of and satisfaction with RM were reported to be high, but the impact of RM on patients’ health-related quality of life, particularly the psychological aspects, was not evaluated thoroughly. Patients who are not technologically competent, having hearing or other physical/mental impairments, were identified as potentially disadvantaged with remote surveillance. Cohort studies consistently identified subgroups of patients who preferred in-office follow-up. The evaluation of costs and workflow impact to the health care system were evaluated in European or American clinical settings, and only in a limited way.
Internet-based device-assisted RMSs involve a new approach to monitoring patients, their disease progression, and their CIEDs. Remote monitoring also has the potential to improve the current postmarket surveillance systems of evolving CIEDs and their ongoing hardware and software modifications. At this point, however, there is insufficient information to evaluate the overall impact to the health care system, although the time saving and convenience to patients and physicians associated with a substitution of in-office follow-up by RM is more certain. The broader issues surrounding infrastructure, impacts on existing clinical care systems, and regulatory concerns need to be considered for the implementation of Internet-based RMSs in jurisdictions involving different clinical practices.
PMCID: PMC3377571  PMID: 23074419
22.  Prognostic factors for disability and sick leave in patients with subacute non-malignant pain: a systematic review of cohort studies 
BMJ Open  2016;6(1):e007616.
This systematic review aims to identify generic prognostic factors for disability and sick leave in subacute pain patients.
General practice and other primary care facilities.
Adults (>18 years) with a subacute (≤3-month) non-malignant pain condition. Eligibility criteria were cohort studies investigating the prediction of disability or long-term sick leave in adults with a subacute pain condition in a primary care setting. 19 studies were included, referring to a total of 6266 patients suffering from pain in the head, neck, back and shoulders.
Primary and secondary outcome measures
The primary outcome was long-term disability (>3 months) due to a pain condition. The secondary outcome was sick leave, defined as ‘absence from work’ or ‘return-to-work’.
PubMed, EMBASE, CINAHL and PEDro databases were searched from 16 January 2003 to 16 January 2014. The quality of evidence was presented according to the GRADE WG recommendations. Several factors were found to be associated with disability at follow-up for at least two different pain symptoms. However, owing to insufficient studies, no generic risk factors for sick leave were identified.
Multiple site pain, high pain severity, older age, baseline disability and longer pain duration were identified as potential prognostic factors for disability across pain sites. There was limited evidence that anxiety and depression were associated with disability in patients with subacute pain, indicating that these factors may not play as large a role as expected in developing disability due to a pain condition. Quality of evidence was moderate, low or very low, implying that confidence in the results is limited. Large prospective prognostic factor studies are needed with sufficient study populations and transparent reporting of all factors examined.
Trial registration number
PMCID: PMC4716223  PMID: 26739716
Prognostic factors; Early detection; Pain
23.  Should General Practitioners Issue a Sick Certificate to Employees Who Consult for Low Back Pain in Primary Care? 
Purpose Back pain is a common problem and has significant societal impact. Sickness certification is commonly issued to patients consulting their general practitioner with low back pain. The aim of this study was to investigate the association of certification for low back pain with clinical outcomes and cost consequences. Methods A prospective cohort study using linked questionnaire and medical record data from 806 low back pain patients in 8 UK general practices: comparison of 116 (14.4 %) who received a sickness certificate versus 690 who did not receive certification. The primary clinical measure was the Roland and Morris Disability Questionnaire (RMDQ). Data on back pain consultation and work absenteeism were used to calculate healthcare and societal costs. Results Participants issued a sickness certificate had higher back-related disability at baseline consultation and 6-month follow-up [mean difference 3.1 (95 % CI 1.8, 4.4) on the RMDQ], indicating worse health status. After fully adjusting for baseline differences, most changes in clinical outcomes at 6 months were not significantly different between study groups. Productivity losses were significantly higher for the certification group, with most absence occurring after the expected end of certification; mean difference in costs due to absenteeism over 6 months was £1,956 (95 % CI £941, £3040). Conclusions There was no clear evidence of a difference in clinical outcomes between individuals issued a sickness certificate and those not issued a certification for their back pain. With little overall contrast in clinical outcomes, policy makers and care providers may wish to draw on the likely difference in societal costs alongside issues in ethical and moral care in their consideration of patient care for low back pain.
PMCID: PMC4540785  PMID: 25595331
Back pain; General practice; Certification; Clinical effectiveness; Cost effectiveness
24.  Prognosis of subacute low back pain patients according to pain response 
European Spine Journal  2007;17(1):57-63.
Centralization of referred pain or failure to centralize has in earlier studies been shown to be a predictor of low back pain prognosis. Research suggests that there are differences in how males and females experience pain. The aim of this study was to evaluate the outcome after 1 year, and to evaluate the prognostic value of the pain response in a mechanical test at the first consultation at a spine clinic, and the influence of gender, in order to identify patients with especially high risk of chronicity. The patients in this study were low back pain patients, included consecutively from a spine clinic in Northern Denmark. The criteria for entering this spine clinic were neck or low back pain with radiating symptoms and a duration of 4–26 weeks, without satisfactory improvement after treatment in the primary care system. The 793 patients were categorised into four subgroups according to their pain response in a mechanical test performed at the initial examination: centralization, non-lasting centralization, peripheralization and no effect. The patients were instructed in doing specific exercises according to the test results. The four subgroups were compared after 1 year with regard to changes in back and leg pain, disability and return-to-work status. The statistical evaluation was undertaken for the study group as a whole and stratified according to gender. A significant improvement in all outcome measures was found in all the subgroups, among both men and women. There were no systematic or statistically significant differences in the prognosis between the four subgroups of patients. The proportion of Centralizers in this study was 18%. The mechanical test at baseline is important for deciding the subject-specific exercises, but when treated according to test results, the prognostic value of the test seems limited.
PMCID: PMC2365517  PMID: 17805584
Low back pain; Prognosis; Mechanical diagnosis and therapy; Directional preference; Gender
25.  Acute Low Back Pain and Primary Care: How to Define Recovery and Chronification? 
Spine  2011;36(26):2316-2323.
Study Design
Prospective cohort study
to establish outcome measures for recovery and chronic pain for studies with patients that present with recent-onset acute low back pain in primary care
Summary of Background Data
Among back pain researchers, no consensus exists about outcome definitions or how to identify primary-care patients as not-recovered from an episode of low back pain. Cut points for outcome scales have mostly been arbitrarily chosen. Theoretical models for establishing minimal important change (MIC) values in studies of patients with low back pain have been proposed and need to be applied to real data.
In a sample of 521 patients which presented with acute low back pain (<4 weeks) in primary care clinics and were followed for 6 months, scores for pain and disability were compared with ratings on a global perceived effect scale. Using multiple potential “gold standards” as anchors (reference standards), the receiver operating characteristics method was used to determine optimal cut points for different ways of defining non-recovery from acute low back pain.
MIC values and upper limits for pain and disability scores as well as minimal important percent changes are presented for five different definitions of recovery. A previously suggested 30% change from baseline scores does not accurately discriminate between recovered and not recovered patients in patients presenting with acute low back pain in primary care.
Outcome definitions that combine ratings from perceived recovery scales with pain and disability measures provide the highest accuracy in discriminating recovered from non-recovered patients.
PMCID: PMC3100452  PMID: 21311400
Acute low back pain; primary care; outcome definitions; minimal important change; receiver operating characteristics

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