Clinical decisions are increasingly driven by evidence-based recommendations of guideline groups, which aim to be based on the highest quality knowledge—randomized clinical trials (RCTs) and meta-analyses. Although RCTs provide the best assessment of the overall value of a therapy, high-quality evidence from RCTs is often incomplete, contradictory, or absent even in areas that have been most exhaustively studied.

Clinical reasoning is the pragmatic, tried-and-true process of expert clinical problem solving that does value mechanistic reasoning and clinical experience as well as RCTs and observational studies. Clinicians must continue to value clinical reasoning if our aim is the best clinical care for all the individuals we treat.