Strategies for Increasing Recruitment to Randomised Controlled Trials: Systematic Review

Abstract

Patrina Caldwell and colleagues performed a systematic review of randomized studies that compared methods of recruiting individual study participants into trials, and found that strategies that focus on increasing potential participants' awareness of the specific health problem, and that engaged them, appeared to increase recruitment.

Increasing boys’ and girls’ intentions to avoid teenage pregnancy: a cluster randomised controlled feasibility trial of an interactive video drama-based intervention in post-primary schools in Northern Ireland

“…Over the years, others have reported that recruitment facilitators include engagement with the target population when developing the intervention and preparing participant information about the study; 106 a personalised and culturally sensitive approach to participants; 99,107 designing recruitment processes that are aimed towards clearly highlighting to potential participants the beneficial outcomes of taking part and addressing any barriers or perceived negative outcomes; 108 providing research and implementation support by providing a dedicated research team contact; 109 minimising the workload for participants by adapting trial processes so they are in line with usual ways of working at the site; 109 providing financial or other incentives; 29 and good communication and expressions of appreciation to site facilitators and participants. 108,109 Although some have suggested the value of using technology such as internet-based questionnaires 110 and the use of video to provide trial information [111][112][113] to improve recruitment, a recent systematic review 98 concluded that their effect is not clear. At the very least, however, the use of video does have obvious benefits in terms of recruiting participants with low literacy levels.…”

Standard 1: Consent and Recruitment

“…Studies reveal that families trust their doctors to explain research, 35,36 and engagement in research may suffer when others are substituted to this role. However, for the clinician to discuss a research study, there should be "clinical equipoise" (genuine uncertainty within the expert medical community) over the research question.…”

Active recruitment and limited participant-load related to high participation in large population-based biobank studies

“…First, face-to-face recruitment is more personal than an invitational letter, a factor that may increase the willingness to participate. Second, face-to-face recruitment makes it easier to emphasize the importance of the study; this has been shown to improve participation rates in randomized controlled trials [8,9]. Studies that followed-up the invitational letter with a phone call also yielded a higher participation rate than studies that only sent an invitational letter.…”