J R Coll Physicians Edinb 2018; 48: 225–232 | doi: 10.4997/JRCPE.2018.306 REVIEW Cognitive bias in clinical medicine ED O’Sullivan1, SJ Schofi eld2 ClinicalCognitive bias is increasingly recognised as an important source of medical Correspondence to: error, and is both ubiquitous across clinical practice yet incompletely ED O’Sullivan Abstract understood. This increasing awareness of bias has resulted in a surge in Department of Renal clinical and psychological research in the area and development of various Medicine ‘debiasing strategies’. This paper describes the potential origins of bias Royal Infi rmary of Edinburgh based on ‘dual process thinking’, discusses and illustrates a number of the 51 Little France Crescent important biases that occur in clinical practice, and considers potential strategies that might Edinburgh EH16 4SA be used to mitigate their effect. UK Keywords: cognitive bias, diagnostic error, heuristics, interventions Email:
[email protected] Financial and Competing Interests: No fi nancial or competing interests declared Introduction Cognitive bias can lead to medical error The human brain is a complex organ with the wonderful An important concept in understanding error is that of power of enabling man to fi nd reasons for continuing to cognitive bias, and the infl uence this can have on our decision- believe whatever it is that he wants to believe. making.10–12 Cognitive biases, also known as ‘heuristics’, are cognitive short cuts used to aid our decision-making. – Voltaire A heuristic can be thought of as a cognitive ‘rule of thumb’ or cognitive guideline that one subconsciously applies to a Cognitive error is pervasive in clinical practice.