Audit and feedback interventions for recruitment and retention in clinical trials: A systematic review

This study had two objectives: (1) to determine the effectiveness of audit and feedback interventions for improving recruitment and retention in randomised controlled trials (hereinafter referred to as trials) and (2) to identify and code behaviour change techniques in the reported audit and feedback interventions.

A systematic review was conducted to identify the effect of audit and feedback intervention (alone or in combination) on participant recruitment and/or retention compared to other strategies. Audit and feedback targeting clinical practice was excluded. Embase and MEDLINE databases were searched up to 9 January 2026. Interventions were coded using Behaviour Change Technique Taxonomy version 1. The results are presented in a narrative form.

Four studies met the eligibility criteria: three randomised and one non-randomised evaluation. Due to the heterogeneity of interventions and outcomes, a meta-analysis was deemed inappropriate. None of the randomised evaluations demonstrated a statistically significant effect of audit and feedback on recruitment outcomes; the non-randomised study reported an increasing trend in recruitment. The risk of bias was low for one and unclear for two trials. The observational study was at a critical risk of bias. None of the studies applied behavior change techniques explicitly. Twenty-one behavior change techniques were identified at least once across both audit and feedback and co-interventions. Ten behavior change techniques were identified in audit and feedback interventions only (mean = 4.8, standard deviation = 2.4). The behavior change technique identified most often in audit and feedback interventions was '2.7. Feedback on outcome(s) of behaviour' (n = 4, 100%; e.g. emails with league tables describing recruitment performance).

This review identified audit and feedback evaluations used to improve recruitment/ retention in a trial context and identified which behavior change techniques are currently used and their frequency. Only one study conceptualised its intervention as audit and feedback and utilised existing audit and feedback literature. Our analysis and behavior change technique coding were restricted to the limited reporting of intervention designs. Further research is needed to understand how audit and feedback is currently being used and whether it can be effective in improving recruitment and retention in trials.