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Reflecting on Diagnostic Errors: Taking a Second Look is Not Enough
Sandra D Monteiro1, Jonathan Sherbino, Ameen Patel
1Clinical Epidemiology and Biostatistics, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4L1, Canada, monteisd@mcmaster.ca.
Background:
An experimenter controlled form of reflection has been shown to improve the detection and correction of diagnostic errors in some situations; however, the benefits of participant-controlled reflection have not been assessed.
Objective:
The goal of the current study is to examine how experience and a self-directed decision to reflect affect the accuracy of revised diagnoses.
Design:
Medical residents diagnosed 16 medical cases (pass 1). Participants were then given the opportunity to reflect on each case and revise their diagnoses (pass 2).
Participants:
Forty-seven medical Residents in post-graduate year (PGY) 1, 2 and 3 were recruited from Hamilton Health Care Centres.
Main Measures:
Diagnoses were scored as 0 (incorrect), 1 (partially correct) and 2 (correct). Accuracies and response times in pass 1 were analyzed using an ANOVA with three factors-PGY, Decision to revise yes/no, and Case 1-16, averaged across residents. The extent to which additional reflection affected accuracy was examined by analyzing only those cases that were revised, using a repeated measures ANOVA, with pass 1 or 2 as a within subject factor, and PGY and Case or Resident as a between-subject factor.
Key Results:
The mean score at pass 1 for each level was PGY1, 1.17 (SE 0.50); PGY2, 1.35 (SE 0.67) and PGY3, 1.27 (SE 0.94). While there was a trend for increased accuracy with level, this did not achieve significance. The number of residents at each level who revised at least one diagnosis was 12/19 PGY1 (63 %), 9/11 PGY2 (82 %) and 8/17 PGY3 (47 %). Only 8 % of diagnoses were revised resulting in a small but significant increase in scores from Pass 1 to 2, from 1.20/2 to 1.22 /2 (t = 2.15, p = 0.03).
Conclusions:
Participants did engage in self-directed reflection for incorrect diagnoses; however, this strategy provided minimal benefits compared to knowing the correct answer. Education strategies should be directed at improving formal and experiential knowledge.
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