What is it?
A questionnaire that covers issues relevant to the trial (e.g., a home safety questionnaire for an injury prevention trial) is added to the trial invitation pack.
Does it work?
Enclosing a questionnaire covering issues relevant to trial with the invitation probably increases recruitment.
How big is the effect?
An increase of 18% (95% confidence interval = 16% to 20%).
How certain are we?
GRADE Moderate certainty.
We recommend that trialists consider enclosing a questionnaire covering issues relevant to the trial with the trial invitation.
How can I use this straight away?
See Resource bundle below for details on how to prepare a questionnaire covering issues relevant to the trial.
Imagine a trial that needs to recruit 30 participants and initial recruitment is 30% of those approached. This means you’d need to approach 100 people to recruit 30 of them (see chart).
Now imagine adding a questionnaire covering issues relevant to the trial to the invitation pack. The chart below shows the impact of an absolute increase of 18% (95% CI = 16% to 20%). Recruitment is now 48%, which means our best estimate is that 63 people would now need to be approached to recruit 30 of them.
*Random effects model done using Comprehensive Meta-Analysis v4 (www.meta-analysis.com).
Differences >0% favour the intervention. The GRADE assessment is moderate because of the imprecision of a single study.
How to Cite
Citation: Treweek S, Bruhn H, Gardner H. Evidence pack– Recruitment: Questionnaire covering issues relevant to the trial (REC11), 2023, https://www.trialforge.org/recruitment-sector/questionnaire-covering-issues-relevant-to-the-trial-rec21
- This summary is from the Cochrane review of strategies to improve recruitment in randomised trials (https://doi.org/10.1002/14651858.MR000013.pub6).
- It was prepared with financial support from Evidence Synthesis Ireland.
- The ‘Does it work?’ statement is structured according to effect size and GRADE certainty as per GRADE Guidelines 26 (https://doi.org/10.1016/j.jclinepi.2019.10.014). The statement is for a large effect size and GRADE Moderate certainty.
- The recommendation statement is the consensus view of the authors of this summary based on the GRADE certainty and features of the trials contributing to the evidence.
- If you have any questions contact email@example.com.