Clinical trial methods for family medicine and primary care.

This article outlines the essential features of clinical trials for doctoral or early career researchers. The World Health Organization has recently emphasised the need for higher quality clinical trials, more trials from low- and middle-income countries, as well as primary care, more engagement with patients and communities and adoption of innovative trial designs. In sub-Saharan Africa, primary care researchers need to move beyond quasi-experimental and before-and-after designs to conduct randomised clinical trials. The article describes the key methodological requirements of a randomised controlled trial: the hypothesis, design, setting, recruitment, randomisation, sample size, intervention, assessment, results, interpretation and extrapolation. We also discuss the aspects of ethical and well-organised trials that respect study participants, engage with collaborative processes, have appropriate governance and transparent dissemination of results. Finally, we outline innovative designs such as step-wedge, clinical trial networks and adaptive platform designs.