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1.  Methods for Specifying the Target Difference in a Randomised Controlled Trial: The Difference ELicitation in TriAls (DELTA) Systematic Review 
PLoS Medicine  2014;11(5):e1001645.
Jonathan Cook and colleagues systematically reviewed the literature for methods of determining the target difference for use in calculating the necessary sample size for clinical trials, and discuss which methods are best for various types of trials.
Please see later in the article for the Editors' Summary
Background
Randomised controlled trials (RCTs) are widely accepted as the preferred study design for evaluating healthcare interventions. When the sample size is determined, a (target) difference is typically specified that the RCT is designed to detect. This provides reassurance that the study will be informative, i.e., should such a difference exist, it is likely to be detected with the required statistical precision. The aim of this review was to identify potential methods for specifying the target difference in an RCT sample size calculation.
Methods and Findings
A comprehensive systematic review of medical and non-medical literature was carried out for methods that could be used to specify the target difference for an RCT sample size calculation. The databases searched were MEDLINE, MEDLINE In-Process, EMBASE, the Cochrane Central Register of Controlled Trials, the Cochrane Methodology Register, PsycINFO, Science Citation Index, EconLit, the Education Resources Information Center (ERIC), and Scopus (for in-press publications); the search period was from 1966 or the earliest date covered, to between November 2010 and January 2011. Additionally, textbooks addressing the methodology of clinical trials and International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) tripartite guidelines for clinical trials were also consulted. A narrative synthesis of methods was produced. Studies that described a method that could be used for specifying an important and/or realistic difference were included. The search identified 11,485 potentially relevant articles from the databases searched. Of these, 1,434 were selected for full-text assessment, and a further nine were identified from other sources. Fifteen clinical trial textbooks and the ICH tripartite guidelines were also reviewed. In total, 777 studies were included, and within them, seven methods were identified—anchor, distribution, health economic, opinion-seeking, pilot study, review of the evidence base, and standardised effect size.
Conclusions
A variety of methods are available that researchers can use for specifying the target difference in an RCT sample size calculation. Appropriate methods may vary depending on the aim (e.g., specifying an important difference versus a realistic difference), context (e.g., research question and availability of data), and underlying framework adopted (e.g., Bayesian versus conventional statistical approach). Guidance on the use of each method is given. No single method provides a perfect solution for all contexts.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
A clinical trial is a research study in which human volunteers are randomized to receive a given intervention or not, and outcomes are measured in both groups to determine the effect of the intervention. Randomized controlled trials (RCTs) are widely accepted as the preferred study design because by randomly assigning participants to groups, any differences between the two groups, other than the intervention under study, are due to chance. To conduct a RCT, investigators calculate how many patients they need to enroll to determine whether the intervention is effective. The number of patients they need to enroll depends on how effective the intervention is expected to be, or would need to be in order to be clinically important. The assumed difference between the two groups is the target difference. A larger target difference generally means that fewer patients need to be enrolled, relative to a smaller target difference. The target difference and number of patients enrolled contribute to the study's statistical precision, and the ability of the study to determine whether the intervention is effective. Selecting an appropriate target difference is important from both a scientific and ethical standpoint.
Why Was This Study Done?
There are several ways to determine an appropriate target difference. The authors wanted to determine what methods for specifying the target difference are available and when they can be used.
What Did the Researchers Do and Find?
To identify studies that used a method for determining an important and/or realistic difference, the investigators systematically surveyed the research literature. Two reviewers screened each of the abstracts chosen, and a third reviewer was consulted if necessary. The authors identified seven methods to determine target differences. They evaluated the studies to establish similarities and differences of each application. Points about the strengths and limitations of the method and how frequently the method was chosen were also noted.
What Do these Findings Mean?
The study draws attention to an understudied but important part of designing a clinical trial. Enrolling the right number of patients is very important—too few patients and the study may not be able to answer the study question; too many and the study will be more expensive and more difficult to conduct, and will unnecessarily expose more patients to any study risks. The target difference may also be helpful in interpreting the results of the trial. The authors discuss the pros and cons of different ways to calculate target differences and which methods are best for which types of studies, to help inform researchers designing such studies.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001645.
Wikipedia has an entry on sample size determination that discusses the factors that influence sample size calculation, including the target difference and the statistical power of a study (statistical power is the ability of a study to find a difference between treatments when a true difference exists). (Note: Wikipedia is a free online encyclopedia that anyone can edit; available in several languages.)
The University of Ottawa has an article that explains how different factors influence the power of a study
doi:10.1371/journal.pmed.1001645
PMCID: PMC4019477  PMID: 24824338
3.  Developing Effective and Efficient care pathways in chronic Pain: DEEP study protocol 
BMC Oral Health  2014;14:6.
Background
Pain affecting the face or mouth and lasting longer than three months (“chronic orofacial pain”, COFP) is relatively common in the UK. This study aims to describe and model current care pathways for COFP patients, identify areas where current pathways could be modified, and model whether these changes would improve outcomes for patients and use resources more efficiently.
Methods/Design
The study takes a prospective operations research approach. A cohort of primary and secondary care COFP patients (n = 240) will be recruited at differing stages of their care in order to follow and analyse their journey through care. The cohort will be followed for two years with data collected at baseline 6, 12, 18, and 24 months on: 1) experiences of the care pathway and its impacts; 2) quality of life; 3) pain; 4) use of health services and costs incurred; 5) illness perceptions. Qualitative in-depth interviews will be used to collect data on patient experiences from a purposive sub-sample of the total cohort (n = 30) at baseline, 12 and 24 months. Four separate appraisal groups (public, patient, clincian, service manager/commissioning) will then be given data from the pathway analysis and asked to determine their priority areas for change. The proposals from appraisal groups will inform an economic modelling exercise. Findings from the economic modelling will be presented as incremental costs, Quality Adjusted Life Years (QALYs), and the incremental cost per QALY gained. At the end of the modelling a series of recommendations for service change will be available for implementation or further trial if necessary.
Discussion
The recent white paper on health and the report from the NHS Forum identified chronic conditions as priority areas and whilst technology can improve outcomes, so can simple, appropriate and well-defined clinical care pathways. Understanding the opportunity cost related to care pathways benefits the wider NHS. This research develops a method to help design efficient systems built around one condition (COFP), but the principles should be applicable to a wide range of other chronic and long-term conditions.
doi:10.1186/1472-6831-14-6
PMCID: PMC3909482  PMID: 24447722
Orofacial pain; Health economics; Quality of life; Qualitative methods; Chronic pain; Care pathways
5.  Issues in the incorporation of economic perspectives and evidence into Cochrane reviews 
Systematic Reviews  2013;2:83.
Background
Methods for systematic reviews of the effects of health interventions have focused mainly on addressing the question of 'What works?’ or 'Is this intervention effective in achieving one or more specific outcomes?’ Addressing the question 'Is it worth it given the resources available?’ has received less attention. This latter question can be addressed by applying an economic lens to the systematic review process.
This paper reflects on the value and desire for the consideration by end users for coverage of an economic perspective in a Cochrane review and outlines two potential approaches and future directions.
Methods
Two frameworks to guide review authors who are seeking to include an economic perspective are outlined. The first involves conducting a full systematic review of economic evaluations that is integrated into a review of intervention effects. The second involves developing a brief economic commentary. The two approaches share a set of common stages but allow the tailoring of the economic component of the Cochrane review to the skills and resources available to the review team.
Results
The number of studies using the methods outlined in the paper is limited, and further examples are needed both to explore the value of these approaches and to further develop them. The rate of progress will hinge on the organisational leadership, capacity and resources available to the CCEMG, author teams and other Cochrane entities. Particular methodological challenges to overcome relate to understanding the key economic trade-offs and casual relationships for a given decision problem and informing the development of evaluations designed to support local decision-makers.
Conclusions
Methods for incorporating economic perspectives and evidence into Cochrane intervention reviews are established. Their role is not to provide a precise estimate of 'cost-effectiveness’ but rather to help end-users of Cochrane reviews to determine the implications of the economic components of reviews for their own specific decisions.
doi:10.1186/2046-4053-2-83
PMCID: PMC3849717  PMID: 24050504
Cost-utility analysis; Cost-effectiveness analysis; Systematic review; Meta-analysis; Cochrane collaboration
6.  Study protocol: longitudinal study of the transition of young people with complex health needs from child to adult health services 
BMC Public Health  2013;13:675.
Background
Young people with complex health needs have impairments that can limit their ability to carry out day-to-day activities. As well as coping with other developmental transitions, these young people must negotiate the transfer of their clinical care from child to adult services. The process of transition may not be smooth and both health and social outcomes may suffer.
Increasingly, policy-makers have recognised the need to ensure a smoother transition between children’s and adult services, with processes that are holistic, individualised, and person-centred; however, there is little outcome data to support proposed models of care. This study aims to identify the features of transitional care that are potentially effective and efficient for young people with complex health needs making their transition.
Methods/Design
Longitudinal cohort study. 450 young people aged 14 years to 18 years 11 months (with autism spectrum disorder and an additional mental health problem, cerebral palsy or diabetes) will be followed through their transition from child to adult services and will contribute data at baseline, 12, 24 and 36 months. We will collect data on: health and wellbeing outcomes (participation, quality of life, satisfaction with services, generic health status (EQ-5D-Y) and condition specific measure of disease control or management); exposure to proposed beneficial features of services (such as having a key worker, appropriate involvement of parents); socio-economic characteristics of the sample; use of condition-related health and personal social services; preferences for the characteristics of transitional care.
We will us regression techniques to explore how outcomes vary by exposure to service features and by characteristics of the young people. These data will populate a decision-analytic model comparing the costs and benefits of potential alternative ways of organising transition services.
In order to better understand mechanisms and aid interpretation, we will undertake qualitative work with 15 young people, including interviews, non-participant observation and diary collection.
Discussion
This study will evaluate the effect of service components of transitional care, rather than evaluation of specific models that may be unsustainable or not generalisable. It has been developed in response to numerous national and international calls for such evaluation.
doi:10.1186/1471-2458-13-675
PMCID: PMC3724698  PMID: 23875722
Transition; Adolescence; Chronic illness; Disability; Evaluation; Protocol
7.  Surgery versus Active Monitoring in Intermittent Exotropia (SamExo): study protocol for a pilot randomised controlled trial 
Trials  2012;13:192.
Background
Childhood intermittent exotropia [X(T)] is a type of strabismus (squint) in which one eye deviates outward at times, usually when the child is tired. It may progress to a permanent squint, loss of stereovision and/or amblyopia (reduced vision). Treatment options for X(T) include eye patches, glasses, surgery and active monitoring. There is no consensus regarding how this condition should be managed, and even when surgery is the preferred option clinicians disagree as to the optimal timing. Reports on the natural history of X(T) are limited, and there is no randomised controlled trial (RCT) evidence on the effectiveness or efficiency of surgery compared with active monitoring. The SamExo (Surgery versus Active Monitoring in Intermittent Exotropia) pilot study has been designed to test the feasibility of such a trial in the UK.
Methods
Design: an external pilot patient randomised controlled trial.
Setting: four UK secondary ophthalmology care facilities at Newcastle NHS Hospitals Foundation Trust, Sunderland Eye Infirmary, Moorfields Eye Hospital and York NHS Trust.
Participants: children aged between 6 months and 16 years referred with suspected and subsequently diagnosed X(T). Recruitment target is a total of 144 children over a 9-month period, with 120 retained by 9-month outcome visit.
Randomisation: permuted blocks stratified by collaborating centre, age and severity of X(T).
Interventions: initial clinical assessment; randomisation (eye muscle surgery or active monitoring); 3-, 6- and 9-month (primary outcome) clinical assessments; participant/proxy completed questionnaire covering time and travel costs, health services use and quality of life (Intermittent Exotropia Questionnaire); qualitative interviews with parents to establish reasons for agreeing or declining participation in the pilot trial.
Outcomes: recruitment and retention rates; nature and extent of participation bias; nature and extent of biases arising from crossover or loss to follow-up; reasons for agreeing/declining participation; variability of cure rates (to inform power calculations for a definitive RCT); completion rates of outcome measures.
Discussion
The SamExo pilot trial will provide important pointers regarding the feasibility of a full RCT of immediate surgery versus deferred surgery/active monitoring. The results of this pilot, including differences in cure rates, will inform the design of a definitive RCT.
Trial registration
ISRCTN44114892
doi:10.1186/1745-6215-13-192
PMCID: PMC3521171  PMID: 23072556
Intermittent exotropia; Divergent strabismus; Surgery; Feasibility studies; Pilot study; Randomised controlled trial; Children; Parents; Qualitative research
8.  Process evaluation for the FEeding Support Team (FEST) randomised controlled feasibility trial of proactive and reactive telephone support for breastfeeding women living in disadvantaged areas 
BMJ Open  2012;2(2):e001039.
Objective
To assess the feasibility, acceptability and fidelity of a feeding team intervention with an embedded randomised controlled trial of team-initiated (proactive) and woman-initiated (reactive) telephone support after hospital discharge.
Design
Participatory approach to the design and implementation of a pilot trial embedded within a before-and-after study, with mixed-method process evaluation.
Setting
A postnatal ward in Scotland.
Sample
Women initiating breast feeding and living in disadvantaged areas.
Methods
Quantitative data: telephone call log and workload diaries. Qualitative data: interviews with women (n=40) with follow-up (n=11) and staff (n=17); ward observations 2 weeks before and after the intervention; recorded telephone calls (n=16) and steering group meetings (n=9); trial case notes (n=69); open question in a telephone interview (n=372). The Framework approach to analysis was applied to mixed-method data.
Main outcome measures
Quantitative: telephone call characteristics (number, frequency, duration); workload activity. Qualitative: experiences and perspectives of women and staff.
Results
A median of eight proactive calls per woman (n=35) with a median duration of 5 min occurred in the 14 days following hospital discharge. Only one of 34 control women initiated a call to the feeding team, with women undervaluing their own needs compared to others, and breast feeding as a reason to call. Proactive calls providing continuity of care increased women's confidence and were highly valued. Data demonstrated intervention fidelity for woman-centred care; however, observing an entire breast feed was not well implemented due to short hospital stays, ward routines and staff–team–woman communication issues. Staff pragmatically recognised that dedicated feeding teams help meet women's breastfeeding support needs in the context of overstretched and variable postnatal services.
Conclusions
Implementing and integrating the FEeding Support Team (FEST) trial within routine postnatal care was feasible and acceptable to women and staff from a research and practice perspective and shows promise for addressing health inequalities.
Trial registration
ISRCTN27207603. The study protocol and final report is available on request.
Article summary
Article focus
To use a participatory approach to design, deliver and implement a feeding support team intervention integrated into routine postnatal ward care and to deliver a pilot randomised controlled trial (RCT) of proactive and reactive telephone support for breast feeding for up to 14 days after hospital discharge for women living in more disadvantaged areas.
To use a mixed qualitative and quantitative methods process evaluation to assess the study acceptability, feasibility and intervention fidelity from the perspectives of women and National Health Service staff.
To inform the design of a future definitive RCT.
Key messages
Women living in disadvantaged areas are unlikely to initiate calls for help with breast feeding and proactive telephone calls may help to counteract the inverse care law.
Women undervalue both breast feeding and their own needs compared with the needs of others as a reason to ask for help in the context of overstretched maternity services.
A caring, reassuring woman-centred communication style with continuity of care from hospital to home was valued and increased women's confidence.
Strengths and limitations of this study
The participatory approach embedding a rigorous RCT within a before-and-after cohort study with mixed-methods data to evaluate implementation processes and costs are strengths that will enable us to design a feasible and acceptable definitive trial.
The contribution of the personal characteristics and skills of the feeding team to the intervention was important and may be challenging to replicate.
The low number of women who reported having an entire breast feed observed is a limitation and warrants further investigation.
More research is required before feeding teams and proactive calls are widely implemented as there are likely to be unintended consequences to such an organisational change in postnatal care.
doi:10.1136/bmjopen-2012-001039
PMCID: PMC3341595  PMID: 22535794
9.  The FEeding Support Team (FEST) randomised, controlled feasibility trial of proactive and reactive telephone support for breastfeeding women living in disadvantaged areas 
BMJ Open  2012;2(2):e000652.
Objective
To assess the feasibility of implementing a dedicated feeding support team on a postnatal ward and pilot the potential effectiveness and cost-effectiveness of team (proactive) and woman-initiated (reactive) telephone support after discharge.
Design
Randomised controlled trial embedded within a before-and-after study. Participatory approach and mixed-method process evaluation.
Setting
A postnatal ward in Scotland.
Sample
Women living in disadvantaged areas initiating breast feeding.
Methods
Eligible women were recruited to a before-and-after intervention study, a proportion of whom were independently randomised after hospital discharge to intervention: daily proactive and reactive telephone calls for ≤14 days or control: reactive telephone calls ≤ day 14. Intention-to-treat analysis compared the randomised groups on cases with complete outcomes at follow-up.
Main outcome measures
Primary outcome: any breast feeding at 6–8 weeks assessed by a telephone call from a researcher blind to group allocation. Secondary outcomes: exclusive breast feeding, satisfaction with care, NHS costs and cost per additional woman breast feeding.
Results
There was no difference in feeding outcomes for women initiating breast feeding before the intervention (n=413) and after (n=388). 69 women were randomised to telephone support: 35 intervention (32 complete cases) and 34 control (26 complete cases). 22 intervention women compared with 12 control women were giving their baby some breast milk (RR 1.49, 95% CI 0.92 to 2.40) and 17 intervention women compared with eight control women were exclusively breast feeding (RR 1.73, 95% CI 0.88 to 3.37) at 6–8 weeks after birth. The incremental cost of providing proactive calls was £87 per additional woman breast feeding and £91 per additional woman exclusively breast feeding at 6–8 weeks; costs were sensitive to service organisation.
Conclusions
Proactive telephone care delivered by a dedicated feeding team shows promise as a cost-effective intervention for improving breastfeeding outcomes. Integrating the FEeding Support Team (FEST) intervention into routine postnatal care was feasible.
Trial registration number
ISRCTN27207603. The study protocol and final report are available on request.
Article summary
Article focus
To pilot the potential effectiveness and cost-effectiveness of continuing proactive and reactive telephone support for breast feeding for up to 14 days after hospital discharge for women living in more disadvantaged areas.
To assess the feasibility of implementing a dedicated feeding team on a postnatal ward.
To design an effective health service intervention for infant feeding by re-organising how routine care is provided to inform a larger programme of research.
Key messages
Proactive telephone care delivered by a dedicated feeding team shows promise for increasing breastfeeding rates 6–8 weeks after birth.
Only having a dedicated feeding team on a postnatal ward did not appear to make any difference to feeding outcomes at 6–8 weeks after birth.
We have demonstrated the feasibility of (1) implementing the FEeding Support Team intervention as part of routine postnatal care and (2) the recruitment and data collection processes for a proposed definitive trial.
Strengths and limitations of this study
Using a participatory approach and embedding a rigorous randomised control trial within a before-and-after cohort study with mixed methods data to evaluate costs are strengths that will enable us to design a definitive trial.
It is likely that the effect sizes are overestimated as the sample size was small and no sample size calculation was performed prior to the study.
Our sample included women requiring longer hospital stays due to birth complications.
The reactive call service was only free to those who had the same mobile phone network provider.
The incremental cost-effectiveness ratios presented represent the most favourable set of assumptions for proactive telephone support and are sensitive to how the service is organised.
doi:10.1136/bmjopen-2011-000652
PMCID: PMC3341594  PMID: 22535790
10.  Systematic Review of Escalated Imatinib Doses Compared with Sunitinib or Best Supportive Care, for the Treatment of People with Unresectable/Metastatic Gastrointestinal Stromal Tumours Whose Disease has Progressed on the Standard Imatinib Dose 
Introduction
We conducted a systematic review of evidence on the effectiveness of imatinib at escalated doses of 600 mg/day or 800 mg/day for treatment of adults with unresectable or metastatic gastrointestinal stromal tumours (GIST), following progression on imatinib at the 400 mg/day dose, compared with sunitinib and/or ‘best supportive care’.
Methods
Electronic searches were undertaken to identify relevant randomised controlled trials (RCTs), non-randomised studies, and case series reporting outcome data on survival, quality of life or adverse events. Titles and abstracts were screened by two reviewers and full text reports of potentially relevant studies assessed for inclusion. Included studies were quality assessed by two reviewers and data were extracted. Five studies reported data on the relevant population and were included.
Results and Discussion
Median overall survival for imatinib (800 mg/day) and sunitinib both were less than 2 years. Around 25% of patients required either an imatinib dose delay or reduction. Approximately one-third of patients receiving dose escalated imatinib (either dose) showed either response or stable disease. Amongst those responding to the escalated 800 mg/day dose, median progression-free survival was over 25 months. The statistical likelihood of response may depend on exon mutational status. There were few data and those that were available were potentially biased, due to their non-randomised nature. Further data are needed to justify international guideline recommendations on imatinib dose escalation.
Conclusion
A prospective audit of management and outcomes for unresectable GIST patients treated with dose escalation upon progression at 400 mg/day may be appropriate as an RCT may be unfeasible.
doi:10.1007/s12029-011-9325-6
PMCID: PMC3348468  PMID: 21971958
GIST; Gastrointestinal stromal tumours; Unresectable; Metastatic; Cancer; Imatinib; Sunitinib
11.  INVESTIGATE-I (INVasive Evaluation before Surgical Treatment of Incontinence Gives Added Therapeutic Effect?): study protocol for a mixed methods study to assess the feasibility of a future randomised controlled trial of the clinical utility of invasive urodynamic testing 
Trials  2011;12:169.
Background
Urinary incontinence is an important health problem to the individual sufferer and to health services. Stress and stress predominant mixed urinary incontinence are increasingly managed by surgery due to advances in surgical techniques. Despite the lack of evidence for its clinical utility, most clinicians undertake invasive urodynamic testing (IUT) to confirm a functional diagnosis of urodynamic stress incontinence before offering surgery for this condition. IUT is expensive, embarrassing and uncomfortable for women and carries a small risk. Recent systematic reviews have confirmed the lack of high quality evidence of effectiveness.
The aim of this pilot study is to test the feasibility of a future definitive randomised control trial that would address whether IUT alters treatment decisions and treatment outcome in these women and would test its clinical and cost effectiveness.
Methods/design
This is a mixed methods pragmatic multicentre feasibility pilot study with four components:-
(a) A multicentre, external pilot randomised trial comparing basic clinical assessment with non-invasive tests and IUT. The outcome measures are rates of recruitment, randomisation and data completion. Data will be used to estimate sample size necessary for the definitive trial.
(b) Qualitative interviews of a purposively sampled sub-set of women eligible for the pilot trial will explore willingness to participate, be randomised and their overall trial experience.
(c) A national survey of clinicians to determine their views of IUT in this context, the main outcome being their willingness to randomise patients into the definitive trial.
(d) Qualitative interviews of a purposively sampled group of these clinicians will explore whether and how they use IUT to inform their decisions.
Discussion
The pilot trial will provide evidence of feasibility and acceptability and therefore inform the decision whether to proceed to the definitive trial. Results will inform the design and conduct of the definitive trial and ensure its effectiveness in achieving its research aim.
Trial registration number
Current Controlled Trials ISRCTN71327395 assigned 7th June 2010.
doi:10.1186/1745-6215-12-169
PMCID: PMC3152523  PMID: 21733166
12.  The effectiveness of early lens extraction with intraocular lens implantation for the treatment of primary angle-closure glaucoma (EAGLE): study protocol for a randomized controlled trial 
Trials  2011;12:133.
Background
Glaucoma is the leading cause of irreversible blindness. Although primary open-angle glaucoma is more common, primary angle-closure glaucoma (PACG) is more likely to result in irreversible blindness. By 2020, 5·3 million people worldwide will be blind because of PACG. The current standard care for PACG is a stepped approach of a combination of laser iridotomy surgery (to open the drainage angle) and medical treatment (to reduce intraocular pressure). If these treatments fail, glaucoma surgery (eg, trabeculectomy) is indicated. It has been proposed that, because the lens of the eye plays a major role in the mechanisms leading to PACG, early clear lens extraction will improve glaucoma control by opening the drainage angle. This procedure might reduce the need for drugs and glaucoma surgery, maintain good visual acuity, and improve quality of life compared with standard care.
EAGLE aims to evaluate whether early lens extraction improves patient-reported, clinical outcomes, and cost-effectiveness, compared with standard care.
Methods/Design
EAGLE is a multicentre pragmatic randomized trial. All people presenting to the recruitment centres in the UK and east Asia with newly diagnosed PACG and who are at least 50 years old are eligible.
The primary outcomes are EQ-5D, intraocular pressure, and incremental cost per quality adjusted life year (QALY) gained. Other outcomes are: vision and glaucoma-specific patient-reported outcomes, visual acuity, visual field, angle closure, number of medications, additional surgery (e.g., trabeculectomy), costs to the health services and patients, and adverse events.
A single main analysis will be done at the end of the trial, after three years of follow-up. The analysis will be based on all participants as randomized (intention to treat). 400 participants (200 in each group) will be recruited, to have 90% power at 5% significance level to detect a difference in EQ-5D score between the two groups of 0·05, and a mean difference in intraocular pressure of 1·75 mm Hg. The study will have 80% power to detect a difference of 15% in the glaucoma surgery rate. Trial Registration: ISRCTN44464607.
doi:10.1186/1745-6215-12-133
PMCID: PMC3121608  PMID: 21605352
13.  Urological cancer care pathways: development and use in the context of systematic reviews and clinical practice guidelines 
World Journal of Urology  2011;29(3):291-301.
Background
Making healthcare treatment decisions is a complex process involving a broad stakeholder base including patients, their families, health professionals, clinical practice guideline developers and funders of healthcare.
Methods
This paper presents a review of a methodology for the development of urological cancer care pathways (UCAN care pathways), which reflects an appreciation of this broad stakeholder base. The methods section includes an overview of the steps in the development of the UCAN care pathways and engagement with clinical content experts and patient groups.
Results
The development process is outlined, the uses of the urological cancer care pathways discussed and the implications for clinical practice highlighted. The full set of UCAN care pathways is published in this paper. These include care pathways on localised prostate cancer, locally advanced prostate cancer, metastatic prostate cancer, hormone-resistant prostate cancer, localised renal cell cancer, advanced renal cell cancer, testicular cancer, penile cancer, muscle invasive and metastatic bladder cancer and non-muscle invasive bladder cancer.
Conclusion
The process provides a useful framework for improving urological cancer care through evidence synthesis, research prioritisation, stakeholder involvement and international collaboration. Although the focus of this work is urological cancers, the methodology can be applied to all aspects of urology and is transferable to other clinical specialties.
doi:10.1007/s00345-011-0660-9
PMCID: PMC3099176  PMID: 21350870
Urological cancer; Care pathways; Systematic review; Clinical practice guidelines
14.  The translation research in a dental setting (TRiaDS) programme protocol 
Background
It is well documented that the translation of knowledge into clinical practice is a slow and haphazard process. This is no less true for dental healthcare than other types of healthcare. One common policy strategy to help promote knowledge translation is the production of clinical guidance, but it has been demonstrated that the simple publication of guidance is unlikely to optimise practice. Additional knowledge translation interventions have been shown to be effective, but effectiveness varies and much of this variation is unexplained. The need for researchers to move beyond single studies to develop a generalisable, theory based, knowledge translation framework has been identified.
For dentistry in Scotland, the production of clinical guidance is the responsibility of the Scottish Dental Clinical Effectiveness Programme (SDCEP). TRiaDS (Translation Research in a Dental Setting) is a multidisciplinary research collaboration, embedded within the SDCEP guidance development process, which aims to establish a practical evaluative framework for the translation of guidance and to conduct and evaluate a programme of integrated, multi-disciplinary research to enhance the science of knowledge translation.
Methods
Set in General Dental Practice the TRiaDS programmatic evaluation employs a standardised process using optimal methods and theory. For each SDCEP guidance document a diagnostic analysis is undertaken alongside the guidance development process. Information is gathered about current dental care activities. Key recommendations and their required behaviours are identified and prioritised. Stakeholder questionnaires and interviews are used to identify and elicit salient beliefs regarding potential barriers and enablers towards the key recommendations and behaviours. Where possible routinely collected data are used to measure compliance with the guidance and to inform decisions about whether a knowledge translation intervention is required. Interventions are theory based and informed by evidence gathered during the diagnostic phase and by prior published evidence. They are evaluated using a range of experimental and quasi-experimental study designs, and data collection continues beyond the end of the intervention to investigate the sustainability of an intervention effect.
Discussion
The TRiaDS programmatic approach is a significant step forward towards the development of a practical, generalisable framework for knowledge translation research. The multidisciplinary composition of the TRiaDS team enables consideration of the individual, organisational and system determinants of professional behaviour change. In addition the embedding of TRiaDS within a national programme of guidance development offers a unique opportunity to inform and influence the guidance development process, and enables TRiaDS to inform dental services practitioners, policy makers and patients on how best to translate national recommendations into routine clinical activities.
doi:10.1186/1748-5908-5-57
PMCID: PMC2920875  PMID: 20646275
15.  A pragmatic multi-centre randomised controlled trial of fluid loading and level of dependency in high-risk surgical patients undergoing major elective surgery: trial protocol 
Trials  2010;11:41.
Background
Patients undergoing major elective or urgent surgery are at high risk of death or significant morbidity. Measures to reduce this morbidity and mortality include pre-operative optimisation and use of higher levels of dependency care after surgery. We propose a pragmatic multi-centre randomised controlled trial of level of dependency and pre-operative fluid therapy in high-risk surgical patients undergoing major elective surgery.
Methods/Design
A multi-centre randomised controlled trial with a 2 * 2 factorial design. The first randomisation is to pre-operative fluid therapy or standard regimen and the second randomisation is to routine intensive care versus high dependency care during the early post-operative period. We intend to recruit 204 patients undergoing major elective and urgent abdominal and thoraco-abdominal surgery who fulfil high-risk surgical criteria. The primary outcome for the comparison of level of care is cost-effectiveness at six months and for the comparison of fluid optimisation is the number of hospital days after surgery.
Discussion
We believe that the results of this study will be invaluable in determining the future care and clinical resource utilisation for this group of patients and thus will have a major impact on clinical practice.
Trial Registration
Trial registration number - ISRCTN32188676
doi:10.1186/1745-6215-11-41
PMCID: PMC2873273  PMID: 20398378
16.  Quality of life in the five years after intensive care: a cohort study 
Critical Care  2010;14(1):R6.
Introduction
Data on quality of life beyond 2 years after intensive care discharge are limited and we aimed to explore this area further. Our objective was to quantify quality of life and health utilities in the 5 years after intensive care discharge.
Methods
A prospective longitudinal cohort study in a University Hospital in the UK. Quality of life was assessed from the period before ICU admission until 5 years and quality adjusted life years calculated.
Results
300 level 3 intensive care patients of median age 60.5 years and median length of stay 6.7 days, were recruited. Physical quality of life fell to 3 months (P = 0.003), rose back to pre-morbid levels at 12 months then fell again from 2.5 to 5 years after intensive care (P = 0.002). Mean physical scores were below the population norm at all time points but the mean mental scores after 6 months were similar to those population norms. The utility value measured using the EuroQOL-5D quality of life assessment tool (EQ-5D) at 5 years was 0.677. During the five years after intensive care unit, the cumulative quality adjusted life years were significantly lower than that expected for the general population (P < 0.001).
Conclusions
Intensive care unit admission is associated with a high mortality, a poor physical quality of life and a low quality adjusted life years gained compared to the general population for 5 years after discharge. In this group, critical illness associated with ICU admission should be treated as a life time diagnosis with associated excess mortality, morbidity and the requirement for ongoing health care support.
doi:10.1186/cc8848
PMCID: PMC2875518  PMID: 20089197
17.  Surgical treatments for men with benign prostatic enlargement: cost effectiveness study 
Objective To determine which surgical treatment for lower urinary tract symptoms suggestive of benign prostate enlargement is cost effective.
Design Care pathways describing credible treatment strategies were decided by consensus. Cost-utility analysis used Markov modelling and Monte Carlo simulation.
Data sources Clinical effectiveness data came from a systematic review and an individual level dataset. Utility values came from previous economic evaluations. Costs were calculated from National Health Service (NHS) and commercial sources.
Methods The Markov model included parameters with associated measures of uncertainty describing health states between which individuals might move at three monthly intervals over 10 years. Successive annual cohorts of 25 000 men were entered into the model and the probability that treatment strategies were cost effective was assessed with Monte Carlo simulation with 10 000 iterations.
Results A treatment strategy of initial diathermy vaporisation of the prostate followed by endoscopic holmium laser enucleation of the prostate in case of failure to benefit or subsequent relapse had an 85% probability of being cost effective at a willingness to pay value of £20 000 (€21 595, $28 686)/quality adjusted life year (QALY) gained. Other strategies with diathermy vaporisation as the initial treatment were generally cheaper and more effective than the current standard of transurethral resection repeated once if necessary. The use of potassium titanyl phosphate laser vaporisation incurred higher costs and was less effective than transurethral resection, and strategies involving initial minimally invasive treatment with microwave thermotherapy were not cost effective. Findings were unchanged by wide ranging sensitivity analyses.
Conclusion The outcome of this economic model should be interpreted cautiously because of the limitations of the data used. The finding that initial vaporisation followed by holmium laser enucleation for failure or relapse might be advantageous both to men with lower urinary tract symptoms and to healthcare providers requires confirmation in a good quality prospective clinical trial before any change in current practice. Potassium titanyl phosphate laser vaporisation was unlikely to be cost effective in our model, which argues against its unrestricted use until further evidence of effectiveness and cost reduction is obtained.
doi:10.1136/bmj.b1288
PMCID: PMC2669854  PMID: 19372131
18.  Clinical and cost-effectiveness of internal limiting membrane peeling for patients with idiopathic full thickness macular hole. Protocol for a Randomised Controlled Trial: FILMS (Full-thickness macular hole and Internal Limiting Membrane peeling Study) 
Trials  2008;9:61.
Background
A full-thickness macular hole (FTMH) is a common retinal condition associated with impaired vision. Randomised controlled trials (RCTs) have demonstrated that surgery, by means of pars plana vitrectomy and post-operative intraocular tamponade with gas, is effective for stage 2, 3 and 4 FTMH. Internal limiting membrane (ILM) peeling has been introduced as an additional surgical manoeuvre to increase the success of the surgery; i.e. increase rates of hole closure and visual improvement. However, little robust evidence exists supporting the superiority of ILM peeling compared with no-peeling techniques. The purpose of FILMS (Full-thickness macular hole and Internal Limiting Membrane peeling Study) is to determine whether ILM peeling improves the visual function, the anatomical closure of FTMH, and the quality of life of patients affected by this disorder, and the cost-effectiveness of the surgery.
Methods/Design
Patients with stage 2–3 idiopathic FTMH of less or equal than 18 months duration (based on symptoms reported by the participant) and with a visual acuity ≤ 20/40 in the study eye will be enrolled in this FILMS from eight sites across the UK and Ireland. Participants will be randomised to receive combined cataract surgery (phacoemulsification and intraocular lens implantation) and pars plana vitrectomy with postoperative intraocular tamponade with gas, with or without ILM peeling. The primary outcome is distance visual acuity at 6 months. Secondary outcomes include distance visual acuity at 3 and 24 months, near visual acuity at 3, 6, and 24 months, contrast sensitivity at 6 months, reading speed at 6 months, anatomical closure of the macular hole at each time point (1, 3, 6, and 24 months), health related quality of life (HRQOL) at six months, costs to the health service and the participant, incremental costs per quality adjusted life year (QALY) and adverse events.
Discussion
FILMS will provide high quality evidence on the role of ILM peeling in FTMH surgery.
Trial registration
This trial is registered with Current Controlled Trials ISRCTN number 33175422 and Clinical Trials.gov identifier NCT00286507.
doi:10.1186/1745-6215-9-61
PMCID: PMC2607251  PMID: 18980675
19.  Alternative approaches to endoscopic ablation for benign enlargement of the prostate: systematic review of randomised controlled trials 
BMJ : British Medical Journal  2008;337(7660):36-39.
Objective To compare the effectiveness and risk profile of newer methods for endoscopic ablation of the prostate against the current standard of transurethral resection.
Design Systematic review and meta-analysis.
Data sources Electronic and paper records in subject area up to March 2006.
Review methods We searched for randomised controlled trials of endoscopic ablative interventions that included transurethral resection of prostate as one of the treatment arms. Two reviewers independently extracted data and assessed quality. Meta-analyses of prespecified outcomes were done using fixed and random effects models and reported using relative risk or weighted mean difference.
Results We identified 45 randomised controlled trials meeting the inclusion criteria and reporting on 3970 participants. The reports were of moderate to poor quality, with small sample sizes. None of the newer technologies resulted in significantly greater improvement in symptoms than transurethral resection at 12 months, although a trend suggested a better outcome with holmium laser enucleation (random effects weighted mean difference −0.82, 95% confidence interval 1.76 to 0.12) and worse outcome with laser vaporisation (1.49, −0.40 to 3.39). Improvements in secondary measures, such as peak urine flow rate, were consistent with change in symptoms. Blood transfusion rates were higher for transurethral resection than for the newer methods (4.8% v 0.7%) and men undergoing laser vaporisation or diathermy vaporisation were more likely to experience urinary retention (6.7% v 2.3% and 3.6% v 1.1%). Hospital stay was up to one day shorter for the newer technologies.
Conclusions Although men undergoing more modern methods of removing benign prostatic enlargement have similar outcomes to standard transurethral resection of prostate along with fewer requirements for blood transfusion and shorter hospital stay, the quality of current evidence is poor. The lack of any clearly more effective procedure suggests that transurethral resection should remain the standard approach.
doi:10.1136/bmj.39575.517674.BE
PMCID: PMC2443595  PMID: 18595932
20.  Randomised trial of glutamine and selenium supplemented parenteral nutrition for critically ill patients. Protocol Version 9, 19 February 2007 known as SIGNET (Scottish Intensive care Glutamine or seleNium Evaluative Trial) 
Trials  2007;8:25.
Background
Mortality rates in the Intensive Care Unit and subsequent hospital mortality rates in the UK remain high. Infections in Intensive Care are associated with a 2–3 times increased risk of death. It is thought that under conditions of severe metabolic stress glutamine becomes "conditionally essential". Selenium is an essential trace element that has antioxidant and anti-inflammatory properties. Approximately 23% of patients in Intensive Care require parenteral nutrition and glutamine and selenium are either absent or present in low amounts. Both glutamine and selenium have the potential to influence the immune system through independent biochemical pathways. Systematic reviews suggest that supplementing parenteral nutrition in critical illness with glutamine or selenium may reduce infections and mortality. Pilot data has shown that more than 50% of participants developed infections, typically resistant organisms. We are powered to show definitively whether supplementation of PN with either glutamine or selenium is effective at reducing new infections in critically ill patients.
Methods/design
2 × 2 factorial, pragmatic, multicentre, double-blind, randomised controlled trial. The trial has an enrolment target of 500 patients. Inclusion criteria include: expected to be in critical care for at least 48 hours, aged 16 years or over, patients who require parenteral nutrition and are expected to have at least half their daily nutritional requirements given by that route.
Allocation is to one of four iso-caloric, iso-nitrogenous groups: glutamine, selenium, both glutamine & selenium or no additional glutamine or selenium. Trial supplementation is given for up to seven days on the Intensive Care Unit and subsequent wards if practicable. The primary outcomes are episodes of infection in the 14 days after starting trial nutrition and mortality. Secondary outcomes include antibiotic usage, length of hospital stay, quality of life and cost-effectiveness.
Discussion
To date more than 285 patients have been recruited to the trial from 10 sites in Scotland. Recruitment is due to finish in August 2008 with a further six months follow up. We expect to report the results of the trial in summer 2009.
Trial registration
This trial is registered with the International Standard Randomised Controlled Trial Number system. ISRCTN87144826
doi:10.1186/1745-6215-8-25
PMCID: PMC2082027  PMID: 17883854
21.  Effect of multivitamin and multimineral supplementation on cognitive function in men and women aged 65 years and over: a randomised controlled trial 
Nutrition Journal  2007;6:10.
Background
Observational studies have frequently reported an association between cognitive function and nutrition in later life but randomised trials of B vitamins and antioxidant supplements have mostly found no beneficial effect. We examined the effect of daily supplementation with 11 vitamins and 5 minerals on cognitive function in older adults to assess the possibility that this could help to prevent cognitive decline.
Methods
The study was carried out as part of a randomised double blind placebo controlled trial of micronutrient supplementation based in six primary care health centres in North East Scotland. 910 men and women aged 65 years and over living in the community were recruited and randomised: 456 to active treatment and 454 to placebo. The active treatment consisted of a single tablet containing eleven vitamins and five minerals in amounts ranging from 50–210 % of the UK Reference Nutrient Intake or matching placebo tablet taken daily for 12 months. Digit span forward and verbal fluency tests, which assess immediate memory and executive functioning respectively, were conducted at the start and end of the intervention period. Risk of micronutrient deficiency at baseline was assessed by a simple risk questionnaire.
Results
For digit span forward there was no evidence of an effect of supplements in all participants or in sub-groups defined by age or risk of deficiency. For verbal fluency there was no evidence of a beneficial effect in the whole study population but there was weak evidence for a beneficial effect of supplementation in the two pre-specified subgroups: in those aged 75 years and over (n 290; mean difference between supplemented and placebo groups 2.8 (95% CI -0.6, 6.2) units) and in those at increased risk of micronutrient deficiency assessed by the risk questionnaire (n 260; mean difference between supplemented and placebo groups 2.5 (95% CI -1.0, 6.1) units).
Conclusion
The results provide no evidence for a beneficial effect of daily multivitamin and multimineral supplements on these domains of cognitive function in community-living people over 65 years. However, the possibility of beneficial effects in older people and those at greater risk of nutritional deficiency deserves further attention.
doi:10.1186/1475-2891-6-10
PMCID: PMC1872030  PMID: 17474991
22.  Toward Evidence-Based Quality Improvement: Evidence (and its Limitations) of the Effectiveness of Guideline Dissemination and Implementation Strategies 1966–1998 
Journal of General Internal Medicine  2006;21(Suppl 2):S14-S20.
OBJECTIVES
To determine effectiveness and costs of different guideline dissemination and implementation strategies.
DATA SOURCES
MEDLINE (1966 to 1998), HEALTHSTAR (1975 to 1998), Cochrane Controlled Trial Register (4th edn 1998), EMBASE (1980 to 1998), SIGLE (1980 to 1988), and the specialized register of the Cochrane Effective Practice and Organisation of Care group.
REVIEW METHODS: INCLUSION CRITERIA
Randomized-controlled trials, controlled clinical trials, controlled before and after studies, and interrupted time series evaluating guideline dissemination and implementation strategies targeting medically qualified health care professionals that reported objective measures of provider behavior and/or patient outcome. Two reviewers independently abstracted data on the methodologic quality of the studies, characteristics of study setting, participants, targeted behaviors, and interventions. We derived single estimates of dichotomous process variables (e.g., proportion of patients receiving appropriate treatment) for each study comparison and reported the median and range of effect sizes observed by study group and other quality criteria.
RESULTS
We included 309 comparisons derived from 235 studies. The overall quality of the studies was poor. Seventy-three percent of comparisons evaluated multifaceted interventions. Overall, the majority of comparisons (86.6%) observed improvements in care; for example, the median absolute improvement in performance across interventions ranged from 14.1% in 14 cluster-randomized comparisons of reminders, 8.1% in 4 cluster-randomized comparisons of dissemination of educational materials, 7.0% in 5 cluster-randomized comparisons of audit and feedback, and 6.0% in 13 cluster-randomized comparisons of multifaceted interventions involving educational outreach. We found no relationship between the number of components and the effects of multifaceted interventions. Only 29.4% of comparisons reported any economic data.
CONCLUSIONS
Current guideline dissemination and implementation strategies can lead to improvements in care within the context of rigorous evaluative studies. However, there is an imperfect evidence base to support decisions about which guideline dissemination and implementation strategies are likely to be efficient under different circumstances. Decision makers need to use considerable judgment about how best to use the limited resources they have for quality improvement activities.
doi:10.1111/j.1525-1497.2006.00357.x
PMCID: PMC2557130  PMID: 16637955
practice guideline; systematic review; implementation research.
23.  Economics methods in Cochrane systematic reviews of health promotion and public health related interventions 
Background
Provision of evidence on costs alongside evidence on the effects of interventions can enhance the relevance of systematic reviews to decision-making. However, patterns of use of economics methods alongside systematic review remain unclear. Reviews of evidence on the effects of interventions are published by both the Cochrane and Campbell Collaborations. Although it is not a requirement that Cochrane or Campbell Reviews should consider economic aspects of interventions, many do. This study aims to explore and describe approaches to incorporating economics methods in a selection of Cochrane systematic reviews in the area of health promotion and public health, to help inform development of methodological guidance on economics for reviewers.
Methods
The Cochrane Database of Systematic Reviews was searched using a search strategy for potential economic evaluation studies. We included current Cochrane reviews and review protocols retrieved using the search that are also identified as relevant to health promotion or public health topics. A reviewer extracted data which describe the economics components of included reviews. Extracted data were summarised in tables and analysed qualitatively.
Results
Twenty-one completed Cochrane reviews and seven review protocols met inclusion criteria. None incorporate formal economic evaluation methods. Ten completed reviews explicitly aim to incorporate economics studies and data. There is a lack of transparent reporting of methods underpinning the incorporation of economics studies and data. Some reviews are likely to exclude useful economics studies and data due to a failure to incorporate search strategies tailored to the retrieval of such data or use of key specialist databases, and application of inclusion criteria designed for effectiveness studies.
Conclusion
There is a need for consistency and transparency in the reporting and conduct of the economics components of Cochrane reviews, as well as regular dialogue between Cochrane reviewers and economists to develop increased capacity for economic analyses alongside such reviews. Use of applicable economics methods in Cochrane reviews can help provide the international context within which economics data can be interpreted and assessed as a preliminary to full economic evaluation.
doi:10.1186/1471-2288-6-55
PMCID: PMC1660547  PMID: 17107612
24.  Overlays or mattresses to prevent pressure sores? 
BMJ : British Medical Journal  2006;332(7555):1401-1402.
PMCID: PMC1479678  PMID: 16777859
25.  Effect of multivitamin and multimineral supplements on morbidity from infections in older people (MAVIS trial): pragmatic, randomised, double blind, placebo controlled trial 
BMJ : British Medical Journal  2005;331(7512):324-329.
Objective To examine whether supplementation with multivitamins and multiminerals influences self reported days of infection, use of health services, and quality of life in people aged 65 or over.
Design Randomised, placebo controlled trial, with blinding of participants, outcome assessors, and investigators.
Setting Communities associated with six general practices in Grampian, Scotland.
Participants 910 men and women aged 65 or over who did not take vitamins or minerals.
Interventions Daily multivitamin and multimineral supplementation or placebo for one year.
Main outcome measures Primary outcomes were contacts with primary care for infections, self reported days of infection, and quality of life. Secondary outcomes included antibiotic prescriptions, hospital admissions, adverse events, and compliance.
Results Supplementation did not significantly affect contacts with primary care and days of infection per person (incidence rate ratio 0.96, 95% confidence interval 0.78 to 1.19 and 1.07, 0.90 to 1.27). Quality of life was not affected by supplementation. No statistically significant findings were found for secondary outcomes or subgroups.
Conclusion Routine multivitamin and multimineral supplementation of older people living at home does not affect self reported infection related morbidity.
Trial registration ISRCTN: 66376460.
PMCID: PMC1183131  PMID: 16081445

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