Letters to the Editor
To the Editor:
We read the article from Sherbino et al1 on the relationship between response time and diagnostic accuracy with great interest. They describe a “System I” heuristic-based and intuitive diagnostic approach that allows physicians to maintain accuracy with speed, and they contend that this approach is not more error-prone than a slower one using analytic thinking. Their conclusion appears valid in the context of a multiple-choice examination, but we feel it is poorly applicable to real-life clinical situations.
Diagnostic decision making often begins before the patient is seen, sometimes with a verbal handoff from another physician or a review of past medical records. Many cognitive biases described by Croskerry2 exert effects before and throughout the patient encounter, influencing what questions are asked, the nature of the physical examination performed, and what diagnostic tests are ordered. In cases where diagnostic errors harm patients, mistakes committed during this initial evaluation have been shown to have greater contributions to the error than mistakes that would be caught by a multiple-choice exam, which are mistakes in synthesizing the diagnosis from a preformed clinical database containing all necessary information.3 In addition, it has been shown that contextual factors absent from a multiple-choice exam contribute significantly to diagnostic errors.4
Further study is desperately needed. Thoughtful investigation—perhaps using simulation technology—of how bias affects the physician’s approach to gathering, organizing, and interpreting diagnostic data seems a logical next step. Until then, we will encourage our learners to embrace System I thinking as a diagnostic approach that has both benefits and limitations, and to be mindful of all its potential to introduce bias to diagnostic decision making.
James B. Reilly, MD, MSHP
Assistant professor of clinical medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; email@example.com.
Joan M. Von Feldt, MD, MS Ed
Professor of medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania.
1. Sherbino J, Dore KL, Wood TJ, et al. The relationship between response time and diagnostic accuracy. Acad Med.. 2012;87:785–791
2. Croskerry P. The importance of cognitive errors in diagnosis and strategies to minimize them. Acad Med. 2003;78:775–780
3. Zwaan L, Thijs A, Wagner C, van der Wal G, Timmermans DR. Relating faults in diagnostic reasoning with diagnostic errors and patient harm. Acad Med. 2012;87:149–156
4. Graber ML, Franklin N, Gordon R. Diagnostic error in internal medicine. Arch Intern Med. 2005;165:1493–1499