How to set go/no-go rules for clinical trial pilot phases to reduce research waste
What is it about?
When researchers run a large clinical trial, they often start with a smaller internal pilot phase to check whether the full study is likely to work. This paper examines how researchers should set "progression criteria" — pre-agreed, measurable targets that determine whether a trial should stop, be adjusted, or continue to full scale. Drawing on a structured literature review and a workshop with trialists, statisticians, methodologists and funders, the authors identify three areas that dominate these decisions: participant recruitment rates, adherence to the study protocol, and the quality of outcome data collection. The paper finds wide variation in current practice and offers ten practical recommendations to help research teams design, apply and report progression criteria more consistently and transparently.
Why is it important?
Clinical trials consume enormous public and charitable research funding, yet many fail or are abandoned because basic feasibility problems go undetected early enough to act on them. Poorly defined or absent progression criteria mean that go/no-go decisions at the end of a pilot phase are made inconsistently, with little transparency, making it harder for the wider research community to learn from those decisions. This paper provides the first systematic framework specifically for internal pilot progression criteria, filling a recognised gap in trial methodology guidance. By standardising how recruitment, protocol adherence and outcome data targets are set and reported, it directly supports more efficient randomised controlled trials, better use of research funding, and faster delivery of reliable evidence to inform clinical practice.