Strengthening evidence-based medicine with real-world evidence

People conducting clinical trials often express concerns that real-world evidence is not reliable enough to form a basis for conclusions about causal relationships, because treatments are neither randomised nor blinded, and real-world data are not subject to the rigorous quality control practices used in randomised controlled trials (RCTs).1 Yet real-world data often are the only source for information about treatment outcomes for patients with complications or other vulnerabilities, such as a high-risk family history, lifestyle factors, limited access to health care, and economic hardship.