Designing randomised controlled trials in rheumatology - What, why, and how

Randomised controlled trials (RCTs) have become the workhorse for evaluating efficacy of various healthcare interventions. The basic plan is to compare the outcome experience of two or more prognostically similar groups of patients with study intervention being the only difference between them. It involves key elements such as random allocation, concealment of allocation, and blinding to guard against design-related biases. This article explains these key features and the steps involved in designing an RCT in the context of rheumatological diseases.