scholarly journals Reducing bias in trials from reactions to measurement: the MERIT study including developmental work and expert workshop

2021 ◽  
Vol 25 (55) ◽  
pp. 1-72
Author(s):  
David P French ◽  
Lisa M Miles ◽  
Diana Elbourne ◽  
Andrew Farmer ◽  
Martin Gulliford ◽  
...  
Keyword(s):  
Systematic Reviews ◽  
Randomised Controlled Trials ◽  
Research Council ◽  
Medical Research Council ◽  
Controlled Trials ◽  
Measurement Reactivity ◽  
Health Related ◽  
Randomised Controlled ◽  
Expert Workshop ◽  
Improve Health

Background Measurement can affect the people being measured; for example, asking people to complete a questionnaire can result in changes in behaviour (the ‘question–behaviour effect’). The usual methods of conduct and analysis of randomised controlled trials implicitly assume that the taking of measurements has no effect on research participants. Changes in measured behaviour and other outcomes due to measurement reactivity may therefore introduce bias in otherwise well-conducted randomised controlled trials, yielding incorrect estimates of intervention effects, including underestimates. Objectives The main objectives were (1) to promote awareness of how and where taking measurements can lead to bias and (2) to provide recommendations on how best to avoid or minimise bias due to measurement reactivity in randomised controlled trials of interventions to improve health. Methods We conducted (1) a series of systematic and rapid reviews, (2) a Delphi study and (3) an expert workshop. A protocol paper was published [Miles LM, Elbourne D, Farmer A, Gulliford M, Locock L, McCambridge J, et al. Bias due to MEasurement Reactions In Trials to improve health (MERIT): protocol for research to develop MRC guidance. Trials 2018;19:653]. An updated systematic review examined whether or not measuring participants had an effect on participants’ health-related behaviours relative to no-measurement controls. Three new rapid systematic reviews were conducted to identify (1) existing guidance on measurement reactivity, (2) existing systematic reviews of studies that have quantified the effects of measurement on outcomes relating to behaviour and affective outcomes and (3) experimental studies that have investigated the effects of exposure to objective measurements of behaviour on health-related behaviour. The views of 40 experts defined the scope of the recommendations in two waves of data collection during the Delphi procedure. A workshop aimed to produce a set of recommendations that were formed in discussion in groups. Results Systematic reviews – we identified a total of 43 studies that compared interview or questionnaire measurement with no measurement and these had an overall small effect (standardised mean difference 0.06, 95% confidence interval 0.02 to 0.09; n = 104,096, I 2 = 54%). The three rapid systematic reviews identified no existing guidance on measurement reactivity, but we did identify five systematic reviews that quantified the effects of measurement on outcomes (all focused on the question–behaviour effect, with all standardised mean differences in the range of 0.09—0.28) and 16 studies that examined reactive effects of objective measurement of behaviour, with most evidence of reactivity of small effect and short duration. Delphi procedure – substantial agreement was reached on the scope of the present recommendations. Workshop – 14 recommendations and three main aims were produced. The aims were to identify whether or not bias is likely to be a problem for a trial, to decide whether or not to collect further quantitative or qualitative data to inform decisions about if bias is likely to be a problem, and to identify how to design trials to minimise the likelihood of this bias. Limitation The main limitation was the shortage of high-quality evidence regarding the extent of measurement reactivity, with some notable exceptions, and the circumstances that are likely to bring it about. Conclusion We hope that these recommendations will be used to develop new trials that are less likely to be at risk of bias. Future work The greatest need is to increase the number of high-quality primary studies regarding the extent of measurement reactivity. Study registration The first systematic review in this study is registered as PROSPERO CRD42018102511. Funding Funded by the Medical Research Council UK and the National Institute for Health Research as part of the Medical Research Council–National Institute for Health Research Methodology Research Programme.

Evidence-Based Practice: The Cochrane Collaboration, and Occupational Therapy

1998 ◽  
Vol 65 (3) ◽  
pp. 144-151 ◽  
Author(s):  
Robyn L. Hayes ◽  
John J. McGrath
Keyword(s):  
Systematic Reviews ◽  
Randomised Controlled Trials ◽  
Best Practice ◽  
Evidence Based Practice ◽  
Occupational Therapists ◽  
Cochrane Collaboration ◽  
Controlled Trials ◽  
Evidence Based ◽  
Randomised Controlled ◽  
The Cochrane Collaboration

This paper describes how occupational therapists can become involved in the Cochrane Collaboration — a well-developed tool for facilitating the involvement of health professionals and lay people in evidence-based practice. The Cochrane Collaboration is a growing international project intended to systematically locate, conduct systematic reviews (including metaanalyses) of, and disseminate information on all available randomised controlled trials of interventions in any area of health. In particular, occupational therapists can use the Cochrane Collaboration to become better informed about best practice and evaluate research in their areas of interest, and learn skills related to conducting randomised controlled trials, systematic reviews, and meta-analyses.

scholarly journals Placebo comparator group selection and use in surgical trials: the ASPIRE project including expert workshop

2021 ◽  
Vol 25 (53) ◽  
pp. 1-52
Author(s):  
David J Beard ◽  
Marion K Campbell ◽  
Jane M Blazeby ◽  
Andrew J Carr ◽  
Charles Weijer ◽  
...  
Keyword(s):  
Randomised Controlled Trials ◽  
Medical Research Council ◽  
Placebo Control ◽  
Controlled Trials ◽  
Surgical Trials ◽  
Surgical Interventions ◽  
Placebo Controls ◽  
Randomised Controlled ◽  
The Uk ◽  
Future Work

Background The use of placebo comparisons for randomised trials assessing the efficacy of surgical interventions is increasingly being considered. However, a placebo control is a complex type of comparison group in the surgical setting and, although powerful, presents many challenges. Objectives To provide a summary of knowledge on placebo controls in surgical trials and to summarise any recommendations for designers, evaluators and funders of placebo-controlled surgical trials. Design To carry out a state-of-the-art workshop and produce a corresponding report involving key stakeholders throughout. Setting A workshop to discuss and summarise the existing knowledge and to develop the new guidelines. Results To assess what a placebo control entails and to assess the understanding of this tool in the context of surgery is considered, along with when placebo controls in surgery are acceptable (and when they are desirable). We have considered ethics arguments and regulatory requirements, how a placebo control should be designed, how to identify and mitigate risk for participants in these trials, and how such trials should be carried out and interpreted. The use of placebo controls is justified in randomised controlled trials of surgical interventions provided that there is a strong scientific and ethics rationale. Surgical placebos might be most appropriate when there is poor evidence for the efficacy of the procedure and a justified concern that results of a trial would be associated with a high risk of bias, particularly because of the placebo effect. Conclusions The use of placebo controls is justified in randomised controlled trials of surgical interventions provided that there is a strong scientific and ethics rationale. Feasibility work is recommended to optimise the design and implementation of randomised controlled trials. An outline for best practice was produced in the form of the Applying Surgical Placebo in Randomised Evaluations (ASPIRE) guidelines for those considering the use of a placebo control in a surgical randomised controlled trial. Limitations Although the workshop participants involved international members, the majority of participants were from the UK. Therefore, although every attempt was made to make the recommendations applicable to all health systems, the guidelines may, unconsciously, be particularly applicable to clinical practice in the UK NHS. Future work Future work should evaluate the use of the ASPIRE guidelines in making decisions about the use of a placebo-controlled surgical trial. In addition, further work is required on the appropriate nomenclature to adopt in this space. Funding Funded by the Medical Research Council UK and the National Institute for Health Research as part of the Medical Research Council–National Institute for Health Research Methodology Research programme.

scholarly journals Outcomes reported on the management of COPD exacerbations: a systematic survey of randomised controlled trials

2019 ◽  
Vol 5 (2) ◽  
pp. 00072-2019 ◽  
Author(s):  
Alexander G. Mathioudakis ◽  
Mia Moberg ◽  
Julie Janner ◽  
Pablo Alonso-Coello ◽  
Jørgen Vestbo
Keyword(s):  
Outcome Measures ◽  
Systematic Reviews ◽  
Randomised Controlled Trials ◽  
Core Outcome Set ◽  
Controlled Trials ◽  
Significant Heterogeneity ◽  
Core Outcome ◽  
Copd Exacerbations ◽  
Outcome Set ◽  
Randomised Controlled

Randomised controlled trials (RCTs) evaluating the management of acute exacerbations of chronic obstructive pulmonary disease (COPD) report heterogeneous outcome measures, thus rendering their results incomparable, complicating their translation into clinical practice. As a first step in the development of a core outcome set that will aim to homogenise outcome measures in future RCTs, we assessed the outcomes reported in recent relevant RCTs and systematic reviews.We conducted a methodological systematic review (https://www.crd.york.ac.uk/prospero/ registration number CRD42016052437) of RCTs and systematic reviews on COPD exacerbation management indexed on Medline and PubMed during the last decade. We evaluated their methodology, specifically focusing on the reported outcome measures.Based on 123 RCTs and 38 systematic reviews, we found significant variability in the outcomes reported and in their definition. Mortality, which was assessed in 82% of the included trials, was the most frequently assessed outcome, followed by the rate of treatment success or failure (63%), adverse events (59%), health status, symptoms and quality of life (59%), lung function (47%), and duration of exacerbations (42%).The significant heterogeneity in the selection and definition of outcome measures in RCTs and systematic reviews limits the interpretability and comparability of their results, and warrants the development of a core outcome set for COPD exacerbations management.

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