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Randomized controlled trials

This chapter on randomized controlled trials (RCTs) considers some of the key factors in the design, conduct, analysis, and interpretation of RCTs. The chapter provides an overview of what constitutes an RCT and why they are needed. The chapter also provides an overview of the major practical elements of the design and conduct of RCTs, including undertaking a background review of literature, the need for formulation of a clear primary hypothesis and objective, selection and definition of the study population, collecting outcomes at baseline and follow-up, and appropriate methods of statistical analysis and inference. The chapter concludes with a consideration of the need for clinical trial units, complex interventions, and alternative RCT designs.