Feasibility studies and pilot trials in behavioral intervention research

OBJECTIVE: Feasibility studies and pilot trials are essential tools in health-related behavioural intervention research. The purposes of this paper are to highlight recent advances in feasibility and pilot trial methodology, examine common deficiencies in pilot trials, and offer solutions that can help to improve the quality and efficiency of intervention research in behavioural medicine. METHODS: Narrative review. RESULTS: In behavioural intervention research, feasibility studies are conducted to determine whether full-fledged efficacy or effectiveness trials can be successfully conducted. Feasibility progression criteria enable investigators to make decisions about readiness to propose a full-fledged trial. Pilot trials are feasibility studies that resemble the anticipated full-fledged trial but with a much smaller sample size. Both internal and external pilot trials are feasibility studies, but they are conducted at different points in the process of intervention research and serve different purposes. Other kinds of early-phase studies are often needed to produce preliminary data about interventions and outcomes that are outside the scope of feasibility aims. CONCLUSION: When properly designed and conducted, feasibility studies and pilot trials can help to ensure the successful completion and improve the quality of clinical trials in health psychology and other fields, as well as to enhance the efficiency of health-related behavioural intervention research.