title: Why do doctors make mistakes? A study of the role of salient distracting clinical features.
abstract: OBJECTIVE
  Diagnostic errors have been attributed to faulty reasoning and cognitive biases, but minimizing errors requires understanding the mechanisms underlying biases. The authors investigated whether salient distracting features (SDFs)-case findings that tend to grab physicians' attention because they are strongly associated with a particular disease, but are indeed unrelated to the problem-misdirect diagnostic reasoning, causing errors.
  
  
  METHODS
  In a 2012 study conducted at Erasmus Medical Centre, Rotterdam, 72 internal medicine residents diagnosed 12 clinical cases (6 simple, 6 complex) in three different formats: without a SDF, with a SDF in the beginning, and with a SDF at the end. In a within-subjects design, each participant solved 2 simple cases and 2 complex cases in each format. Proportions of correct diagnoses in each case type were compared by performing repeated-measures analysis of variance (ANOVA).
  
  
  RESULTS
  There was a significant main effect of SDFs and a significant interaction effect between SDFs and case complexity. The presence of SDFs in the beginning of complex cases caused errors decreasing the proportion of correct diagnoses in comparison both with cases without SDFs (0.18, 95% CI, 0.13-0.23 versus 0.43, 95% CI, 0.35-0.51; P < .001) or with SDFs at the end (0.18, 95% CI, 0.13-0.23 versus 0.36, 95% CI, 0.29-0.43; P < .001). SDFs did not affect performance when presented near the end of cases.
  
  
  CONCLUSIONS
  SDFs early in a case are apparently an important source of diagnostic errors. Physicians should be aware of the need to overcome their influence.
authors.affiliation: Dr. Mamede is associate professor, Institute of Medical Education Research Rotterdam, Erasmus Medical Centre, and associate professor, Department of Psychology, Erasmus University, Rotterdam, The Netherlands. Dr. van Gog is professor, Department of Psychology, Erasmus University, Rotterdam, The Netherlands. Dr. van den Berge is resident, Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, The Netherlands. Dr. van Saase is professor, Department of Internal Medicine, Erasmus University, Rotterdam, The Netherlands. Dr. Schmidt is professor, Department of Psychology, Erasmus University, Rotterdam, The Netherlands.
authors.forename: Sílvia
authors.initials: S
authors.lastname: Mamede
authors.forename: Tamara
authors.initials: T
authors.lastname: van Gog
authors.forename: Kees
authors.initials: K
authors.lastname: van den Berge
authors.forename: Jan L C M
authors.initials: JL
authors.lastname: van Saase
authors.forename: Henk G
authors.initials: HG
authors.lastname: Schmidt
mesh_terms: D000328:Adult; D002983:Clinical Competence; D003657:Decision Making; D003951:Diagnostic Errors; D004503:Education, Medical, Graduate; D005260:Female; D006801:Humans; D007388:Internal Medicine / Q000193:education*; D007396:Internship and Residency; D008297:Male; D009426:Netherlands; D012307:Risk Factors