What influences communication about retention in randomised trials: a multi-trial, theory-based analysis exploring trial staff perspectives

BACKGROUND: Retention (participants completing a trial) is a persistent, and often under-studied, challenge within clinical trials. Research on retention has focussed on understanding the actions of participants who decide to remain or withdraw from trial participation and developing interventions to target improvements. To better understand how trial staff may influence participants to remain or withdraw from trials, it is important to explore the experiences of staff that recruit and retain said participants and how the process of recruitment impacts retention.

METHODS: Two qualitative interview studies informed by the Theoretical Domains Framework (TDF) were conducted with staff involved in various stages of clinical trials. The first set of interviews were focussed on staff perceptions about why participants failed to be retained and what helped to keep others engaged in trials, but also explored more generally what strategies or factors contributed to retention in trials. The second set of interviews were focussed on staff perceptions specifically about the recruitment and informed consent process and how that may influence trial retention. All interviews were analysed using the TDF and assigned to relevant behavioural domains according to perceived barriers/facilitators of the target behaviour. Belief statements were generated, summarising the narrative content of related responses within these behavioural domains. These belief statements were further analysed for themes that captured higher order relationships between separate beliefs within and between behavioural domains.

RESULTS: Twenty-five participants (9 retention staff and 16 recruitment staff) were interviewed. Themes describing the barriers/facilitators to retention broadly, and to communication of retention information at consent, were generated. Four themes on retention broadly and six themes on communication of retention information at consent were identified. Overall, beliefs within all fourteen TDF domains populated these themes.

CONCLUSIONS: This study explored staff perspectives on retention and how they interpret their behaviour as contributing to retention success. Perspectives varied considerably but several key themes regarding communication were seen consistently. Specific barriers and facilitators within these findings will serve to guide the design of a behavioural intervention aimed at addressing issues within retention. Findings contribute to a notable gap in the literature on staff behaviour in trials and on retention generally.