Meeting the Challenges of Recruiting and Retaining Families in a Pragmatic Randomised Controlled Trial of the Strengthening Families Programme 10-14 UK

Introduction: Trials of family-based prevention interventions often face challenges in recruitment and retention, leading to methodological issues. However, little research exists on what causes poor recruitment and retention, and the effectiveness of strategies to address these problems, resulting in a lack of guidance for researchers. This study is one of the first comprehensive reports of the challenges and remedial strategies pertinent to recruiting and retaining families in a family-based prevention trial. Using the example of the first UK trial of the Strengthening Families Programme 10-14 (SFP), it aims to: describe factors influencing trial recruitment and retention; report how recruitment and retention rates were maximised, and describe the recruitment and retention rates achieved.

Methods: Qualitative data examining factors influencing trial recruitment and retention were collected through research reports completed by fieldworkers who conducted 24-month interviews with families and through interviews and focus groups conducted with staff who delivered the SFP, and fieldworkers who recruited families into the trial. Qualitative data were subjected to thematic analysis. Descriptive information about methods developed to maximise trial retention were obtained from the trial protocol and retention strategy. Quantitative data captured during routine monitoring of trial recruitment were used to assess the extent to which the target sample size was achieved and retained.

Results: A number of factors affected trial recruitment. For example, practitioners were unfamiliar with experimental research and had some concerns about the ethics of randomisation. Existing recruitment systems were geared towards targeted recruitment resulting in difficulties recruiting a universal population. Practical issues such as being able to re-contact families who had expressed an interest in the trial also created challenges. Strategies used to improve recruitment included employing additional staff, extending the study duration and spending time engaging local practitioners. The trial successfully recruited 715 (931 children) of the target 756 families (945 children). Strategies to maximise retention included using various methods of contacting families, for example, via schools, and skipping some data collection in favour of the collection of the primary outcome at 24 month follow-up. Retention at 24 months was 81.4% for children and 75.4% for adults.

Conclusion: In this trial of the SFP, multiple methods were used to achieve high recruitment and retention rates. Key to the success was partnership working with local delivery agencies, referrers, and funders. The implications of these findings for the design and implementation of other similar trials will be discussed.