Search

Background: Most incorrect diagnoses involve at least one cognitive error, of which premature closure is the most prevalent. While metacognitive strategies can mitigate premature closure in inexperienced learners, these are rarely studied in experienced physicians. Our objective here was to evaluate the effect of analytic information processing on diagnostic performance of nephrologists and nephrology residents. Methods: We asked nine nephrologists and six nephrology residents at the University of Calgary and Glasgow University to diagnose ten nephrology cases. We provided presenting features along with contextual information, after which we asked for an initial diagnosis. We then primed participants to use either hypothetico-deductive reasoning or scheme-inductive reasoning to analyze the remaining case data and generate a final diagnosis. Results: After analyzing initial hypotheses, both nephrologists and residents improved the accuracy of final diagnoses (31.1% vs. 65.6%, p < 0.001, and 40.0% vs. 70.0%, p < 0.001, respectively). We found a significant interaction between experience and analytic processing strategy (p = 0.002): nephrology residents had significantly increased odds of diagnostic success when using scheme-inductive reasoning (odds ratio [95% confidence interval] 5.69 [1.59, 20.33], p = 0.007), whereas the performance of experienced nephrologists did not differ between strategies (odds ratio 0.57 [0.23, 1.39], p = 0.2). Discussion: Experienced nephrologists and nephrology residents can improve their performance by analyzing initial diagnostic hypotheses. The explanation of the interaction between experience and the effect of different reasoning strategies is unclear, but may relate to preferences in reasoning strategy, or the changes in knowledge structure with experience.

Background: Studies suggest that residents tend to accept diagnostic suggestions, which could lead to diagnostic errors if the suggestion is incorrect. Those studies did not take into account that physicians in clinical practice will mainly encounter correct suggestions. The present study investigated residents’ diagnostic performance if they would first encounter a number of correct suggestions followed by a number of incorrect suggestions, and vice versa. It was hypothesized that more incorrect suggestions would be accepted if participants had first evaluated a series of correct suggestions. Method: Residents (n = 38) evaluated suggested diagnoses on eight written clinical cases. Half of the participants first evaluated four correct suggestions and then evaluated four incorrect suggestions (C/I-condition). The other half started with the four incorrect suggestions followed by the correct suggestions (I/C-condition). Results: Our findings show that the evaluation score in the C/I condition (M = 2.87, MSE = 0.14) equaled that in the I/C condition (M = 2.66, MSE = 0.14), F(1,36) = 1.09, p = 0.30, ns, meaning that consistency in preceding suggested diagnoses did not influence the tendency to accept subsequent diagnostic suggestions. There was, however, a significant interaction effect between case order and phase, F(1,36) = 11.82, p = 0.001, ηp2 = 0.25, demonstrating that the score on cases with correct suggestions was higher than the score on cases with incorrect suggestions. Conclusion: These findings indicate that consistency in preceding correct or incorrect diagnostic suggestions did not influence the tendency to accept or reject subsequent suggestions. However, overall residents still showed a tendency to accept diagnostic suggestions, which may lead to diagnostic errors if the suggestion is incorrect.

Introduction. If physicians apply clinical rather than biomedical knowledge when diagnosing, why do we use the basic sciences as the foundation for clinical teaching? In this study we evaluated the contribution of biomedical knowledge to diagnostic performance when solving electrolyte problems. Method. We asked 13 medical students and 19 nephrologists to solve electrolyte problems while thinking aloud, and determined biomedical knowledge application by protocol analysis. We used logistic regression to study the association between biomedical concepts, clinical experience, and performance. Results. Students and nephrologists applied a similar number of biomedical concepts per case (1.8 (±1.1) vs. 1.8 (±1.2), respectively, p = 0.8), but nephrologists were more successful (86.8% vs. 63.5%, p = 0.003). We found a significant interaction between expertise and applying biomedical concepts (p < 0.05). For students the odds of success increased significantly with applying biomedical concepts (odds ratio 4.66 [2.07, 10.48], p < 0.001), whereas for nephrologists there was only a trend towards improved performance (odds ratio 1.72 [0.94, 3.11], p = 0.07). Conclusions. Our results suggest that improving biomedical knowledge of students should improve their performance on electrolyte problems. The performance of experienced physicians may also be improved, but this requires further study before teaching recommendations can be made.