Purpose: Reflection in medical diagnosis has been said to prevent errors by minimizing flaws in clinical reasoning. This claim, however, has been much disputed. While some studies show reflective reasoning to improve diagnostic performance, others find it to add nothing. This paper presents a narrative review of the literature on reflection in medical diagnosis aimed at addressing two questions: (1) how reflective reasoning has been conceived in this literature; and (2) what is the effect of different forms of reflective reasoning on diagnostic performance.

Method: We searched PubMed and Web of Science for papers published until June 2016 and identified additional literature through the list of references from the initial publications. By building upon dual-processing theories of reasoning, we classified the empirical studies according to two dimensions: (1) the phase of the diagnostic process in which reflection was applied, and (2) the type of reasoning instructions provided to participants.

Results: We identified 46 papers for full review, 31 of them reporting on empirical studies. Different conceptualizations of reflective reasoning exist in the literature. In 16 studies, reflective reasoning was triggered to verify previously generated diagnosis, usually (13/16 studies) by following specific reasoning instructions. Participants were requested to reflect for generating diagnostic hypothesis in 4 studies, all using specific instructions. In 8 studies, 2 of them employing specific instructions, reflection was assumed as taking place throughout the diagnostic process. Reflective reasoning positively affected diagnostic performance when conceived as a process of examining the grounds of initial diagnoses generated through intuitive judgment. The benefits of reflection were particularly substantial when physicians were provided with specific reasoning instructions that led them to be confronted with evidence from the case. Studies using other forms of reflection led to contradictory findings.

Discussion: Reflective reasoning can be a powerful tool to reduce diagnostic errors and increase diagnostic performance. For this to happen, reflection should be triggered for diagnosis verification and needs to interfere with initial diagnostic reasoning, which requires confrontation with evidence from the case