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Methods to improve recruitment to randomised controlled trials: Cochrane systematic review and meta-analysis
Shaun Treweek1, Pauline Lockhart, Marie Pitkethly
1Division of Population Health Sciences, University of Dundee, Dundee, UK.
BMJ Open
|February 12, 2013
Summary
Effective strategies for improving clinical trial recruitment include telephone reminders and opt-out procedures. However, some methods like open-trial designs require careful consideration due to potential methodological and ethical challenges.
Area of Science:
- Clinical Research Methodology
- Evidence-Based Medicine
- Trial Recruitment Strategies
Background:
- Recruitment is a critical challenge in randomized controlled trials (RCTs).
- Identifying effective interventions to improve participant enrollment is essential for trial success.
- Previous reviews have explored various recruitment strategies.
Purpose of the Study:
- To systematically review and quantify the effectiveness of interventions aimed at enhancing recruitment to randomized controlled trials (RCTs).
- To identify which strategies most significantly impact trial participation rates.
Main Methods:
- Systematic review of randomized and quasi-randomized controlled trials.
- Searches conducted across multiple databases including MEDLINE, EMBASE, and PubMed up to 2010.
- Included studies focused on interventions for potential trial participants and recruiters, excluding retention strategies.
Main Results:
- 45 trials involving over 43,000 participants were analyzed.
- Telephone reminders to non-respondents (RR 1.66) and opt-out procedures (RR 1.39) significantly increased recruitment.
- Open-trial designs also showed a positive effect (RR 1.22), though other strategies like video information and recruiter interventions had unclear impacts.
Conclusions:
- Several promising strategies exist to boost trial recruitment, including telephone reminders and opt-out methods.
- Open-trial designs and opt-out strategies warrant careful consideration due to potential methodological and ethical implications.
- Further research is needed to address knowledge gaps concerning recruiter-focused strategies and the generalizability of findings from hypothetical trials.
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