Making Decisions in the Era of the Clinical Decision Rule: How Emergency Physicians Use Clinical Decision Rules

Physicians are often asked to integrate clinical decision rules (CDRs) with their own cognitive processes to reach a diagnosis. Clinicians, researchers, and educators must understand these cognitive processes to evaluate and improve the diagnostic process. The authors sought to explore emergency physicians' diagnostic processes and to examine how they integrated CDRs into their reasoning using simulated cases (with chest pain or leg pain).

From August 2015 to July 2016, 16 practicing emergency physicians from 3 teaching hospitals associated with McMaster University, Ontario, Canada, were interviewed via a novel "teach aloud" protocol. Six videos of simulated patients with chest pain, breathlessness, or leg discomfort were used as prompts for the physicians to demonstrate their diagnostic thinking. Using a constructivist grounded theory analysis, 3 investigators independently reviewed the interview transcripts, meeting regularly to discuss identified themes and subthemes until sufficiency was reached.

A model to describe how clinicians integrate their own decision making with CDRs was developed, showing that physicians engage in an iterative diagnostic process that repeatedly refines the differential diagnosis list. The steps in the diagnostic process were: refinement of the differential diagnosis, ordering a hierarchy of risk, the decision to test, choosing the tests, and interpreting test results. Physicians applied CDRs when they had already decided to test.

To date, CDRs assume a static, linear model of clinical decision making. Findings demonstrate that participants engaged in iterative and dynamic decision-making processes that changed throughout their patient encounter, contingent on multiple contextual features. Understanding these processes could inform future development of CDRs and educational strategies around these decision aids.