Brief Reports| Volume 57, ISSUE 2, P168-172, August 2019

Cognitive Biases in Emergency Physicians: A Pilot Study



      Cognitive bias can lead to systematic errors in judgment.


      We sought to assess cognitive bias in emergency physicians and compare the results to a sample of nonphysicians.


      Selected emergency physicians were invited to take the Rationality Quotient (RQ) test, which measures cognitive biases. Control subjects were nonphysicians selected randomly from individuals who had taken the RQ test contemporaneously. We compared RQ scores overall and by bias and assessed the relationship between self-reported statistical knowledge and familiarity with decision-making biases and RQ scores.


      Of 150 physicians invited, 95 (63%) completed the RQ test. There was less bias in physicians compared with control subjects (RQ scores were 51.1 for physicians and 43.3 for control subjects, p < 0.001). There was less bias among physicians for both bias blind spot (15 vs. 14.3, p < 0.001) and for representative bias (10.4 vs. 5.2, p < 0.001). Anchoring bias, confirmation bias, projection bias, and attribution error were not significantly different. Emergency physicians with greater self-reported statistical familiarity (either 6 of 7 or 7 of 7 on a Likert scale) had higher RQ scores by 7.7 points (95% confidence interval 3.1–12.3)—i.e., they were less biased. There was no association between self-reported knowledge of decision biases and RQ scores.


      Cognitive biases were common in this sample of emergency physicians, and physicians demonstrated less bias than control subjects. Variability was mostly attributed to 2 biases: bias blind spot and representative bias.


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