How are progression decisions made following external randomised pilot trials? A qualitative interview study and framework analysis

BACKGROUND: External randomised pilot trials help researchers decide whether, and how, to do a future definitive randomised trial. The progression criteria are often prespecified to inform the interpretation of pilot trial findings and subsequent progression decision-making. We aimed to explore and understand the perspectives and experiences of key stakeholders when making progression decisions following external pilot trials. METHODS: Thirty-five remote semi-structured interviews with external randomised pilot trial team members including chief investigators, trial managers, statisticians and patient and public involvement (PPI) representatives. Questions focussed on experiences and perceptions of pilot trial progression decisions and whether and how progression criteria informed this decision. Data were analysed using the framework method approach to thematic analysis. Strategies to ensure trustworthiness and rigour were used. RESULTS: Interviews were conducted between December 2020 and July 2021. Six descriptive themes were developed to capture the experiences and perspectives of participants. These were (1) divided opinions on the value and development of progression criteria, (2) (avoiding) the potential for personal interest to influence progression criteria and progression decision-making, (3) stakeholder engagement in setting progression criteria and making progression decisions, (4) lessons learned from doing the pilot trial and their impact on progression criteria applicability, (5) other factors that inform the progression decision and (6) progression of external randomised pilot trials—funding considerations and constraints. These themes were underpinned by an overarching interpretative theme ‘a one-size approach to progression does not fit all’ to describe the highly nuanced and complex decision-making process that occurs following external randomised pilot trials. The progression criteria are rarely the only consideration informing the decision to progress to future research; unanticipated events, signals of efficacy and continuity of the research team are other factors that researchers consider. CONCLUSIONS: One size does not fit all when it comes to the progression criteria and pilot trial progression. The progression criteria are only one of many considerations researchers have when deciding whether a pilot trial is feasible. External pilot trial progression is not guaranteed even when a pilot trial is considered feasible (based on the progression criteria and/or other considerations), indicating inefficiency and potential research waste. TRIAL REGISTRATION: Open Science Framework osf.io/5N2KZ SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13063-022-06063-9.