396 papers were retrieved and 37 studies were included in this review.
Recruitment strategies that improved recruitment included:
- increased people's awareness of the health problem being studied (e.g., an interactive computer program)
- attendance at an education session
- addition of a health questionnaire or a video about the health condition
- monetary incentives
Increasing patients' understanding of the trial process, recruiter differences, and various methods of randomisation and consent design did not show a difference in recruitment.
References:
Caldwell PHY, Hamilton S, Tan A, Craig JC (2010) Strategies for Increasing Recruitment to Randomised Controlled Trials: Systematic Review. PLoS Med 7(11): e1000368. doi:10.1371/journal.pmed.1000368
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