How Doctors Think defines the nature and importance of clinical judgment. Although physicians make use of science, this book argues that medicine is not itself a science but rather an interpretive practice that relies on clinical reasoning. A physician looks at the patient's history along with the presenting physical signs and symptoms and juxtaposes these with clinical experience and empirical studies to construct a tentative account of the illness.
How Doctors Think is divided into four parts. Part one introduces the concept of medicine as a practice rather than a science; part two discusses the idea of causation; part three delves into the process of forming clinical judgment; and part four considers clinical judgment within the uncertain nature of medicine itself. In How Doctors Think, Montgomery contends that assuming medicine is strictly a science can have adverse side effects, and suggests reducing these by recognizing the vital role of clinical judgment.