Behavioural interventions to improve clinical trial recruitment and retention

Behavioural interventions to improve clinical trial recruitment and retention

PhD Project - Dr Taylor Coffey

Randomized clinical trials are at the heart of evidence-based healthcare. A common impediment to conducting a rigorous and unbiased trial is the complementary processes of recruitment and retention. The goal of any trialist is to recruit an acceptable number of participants and have those participants matriculate through to trial completion. However, the reality of most clinical trials is that there will be a significant portion of participants that prematurely withdraw [1], and this loss of data has serious implications for the credibility of the overall trial’s results [2]. As many as half of all clinical trials are at risk of having their results upended if the data from these non-retainers was known [2]. It is therefore imperative that clinical trials researchers and methodologists understand what is behind these pervasive issues with maintaining participants on trials.

This PhD intends to better understand how the interconnected processes of recruitment and retention to trials can be informed by theoretical approaches to behavioural interventions. To do so, the project will entail the following:

A systematic mapping review of the literature to look at what behavioural theories have been used within the context of trial recruitment and retention and how have these been applied (submitted for publication)

An empirical project looking to understand, and develop solutions to, issues relating to retention that stem from behaviours during trial recruitment. This project is known as TRAC-RETAIN (Trial Recruiter Approaches to Communication of RETention At INformed consent) and is broken down into the following objectives:

Objective 1:

We will conduct semi-structured interviews informed by the Behaviour Change Wheel (BCW) and the Theoretical Domains Framework (TDF) to explore trial recruiters’ experiences of verbally communicating trial retention information during recruitment conversations preceding informed consent and randomisation. To this end, we will identify trial recruiters, i.e. those who are the members of a study team that discuss participation in a trial with a potential participant, from both sites that are performing as expected as well as those that need improvement within ongoing clinical trials. Previously recorded recruitment discussions, patient information leaflets (PILs), and other documents relevant to recruitment (e.g. “top tips”, training guidance, recruitment FAQs) from other trials will also be analysed.

Objective 2: 

Behaviour change techniques (BCTs) will be identified from relevant domains identified in the interviews and brought forward to a co-design group. This group will consist of trial recruiters and patient representatives and will assist us in packaging the BCTs into interventions. 

Objective 3: 

The interventions developed during Objective 2 will be piloted with trial recruiters, research ethics committee members, and patient representatives in focus groups to determine their feasibility and acceptability. 

Supervisors: Dr. Katie Gillies, Dr. Eilidh Duncan, and Dr. Heather Morgan


Walsh M, Sackett D, Deveraux PJ. When RCT participants are lost to follow up. Why even a few can matter. Clin Trials. 2015;12:537–9. 

Walsh M, Srinathan SK, McAuley DF, Mrkobrada M, Levine O, Ribic C, Molnar AO, Dattani ND, Burke A, Guyatt G, Thabane L, Walter SD, Pogue J, Devereaux PJ. The statistical significance of randomized controlled trial results is frequently fragile: a case for a Fragility Index. J Clin Epidemiol. 2014;67(6):622–8.





Coffey T, Duncan EM, Morgan H, Lawrie L and Gillies K Behavioural approaches to recruitment and retention in clinical trials: a systematic mapping review BMJ Open 2022;12:e054854. doi: 10.1136/bmjopen-2021-054854

Coffey T, Duncan EM, Morgan H and Gillies K What influences communication about retention in randomised trials: a multi-trial, theory-based analysis exploring trial staff perspectives. BMC Med Res Methodol 22, 231 (2022).