Teaching from the clinical reasoning literature: combined reasoning strategies help novice diagnosticians overcome misleading information.

OBJECTIVE: Previous research has revealed a pedagogical benefit of instructing novice diagnosticians to utilise a combined approach to clinical reasoning (familiarity-driven pattern recognition combined with a careful consideration of the presenting features) when diagnosing electrocardiograms (ECGs). This paper reports 2 studies demonstrating that the combined instructions are especially valuable in helping students overcome biasing influences. METHODS: Undergraduate psychology students were trained to diagnose 10 cardiac conditions via ECG presentation. Half of all participants were instructed to reason in a combined manner and half were given no explicit instruction regarding the diagnostic task. In Study 1 (n = 60), half of each group was biased towards an incorrect diagnosis through presentation of counter-indicative features. In Study 2 (n = 48), a third of the test ECGs were presented with a correct diagnostic suggestion, a third with an incorrect suggestion, and a third without a suggestion. RESULTS: Overall, the instruction to utilise a combined reasoning approach resulted in greater diagnostic accuracy relative to leaving students to their own intuitions regarding how best to approach new cases. The effect was particularly pronounced when cases were made challenging by biasing participants towards an incorrect diagnosis, either through mention of a specific feature or by making an inaccurate diagnostic suggestion. DISCUSSION: These studies advance a growing body of evidence suggesting that various diagnostic strategies identified in the literature on clinical reasoning are not mutually exclusive and that trainees can benefit from explicit guidance regarding the value of both analytic and non-analytic reasoning tendencies.

Practice makes perfect: the critical role of mixed practice in the acquisition of ECG interpretation skills.

PURPOSE: To examine the effect of instructional format on medical students' learning of ECG diagnosis. METHOD: Two experiments employed different learning and practice methods. In the first, students were randomly allocated to one of two instructional approaches, one organized around features (e.g., QRS voltage) and the other around diagnostic categories (e.g., bundle branch blocks), followed by a practice phase. In the second experiment, the instruction was standardized, and students were randomly allocated to one of two practice phases, either "contrastive" where examples from various categories are mixed together, or "non-contrastive" where all the examples in a single category are practiced in a single block. RESULTS: In the first experiment, there was no significant differences in students' diagnostic accuracy on novel ECG examples. In the second experiment, students exposed to the contrastive approach in the practice phase had superior diagnostic accuracy (46%) compared to 30% accuracy for the non-contrastive session, p < 0.05). CONCLUSION: These experiments highlight two important features in the design of instructional materials. First, learning around the features of the problem (analogous to problem-based learning) may have no advantages over learning the category. Second, the design and organization of deliberate practice can result in significant learning gain.

Self and peer assessment in tutorials: application of a relative-ranking model.

PURPOSE: While self assessment continues to be touted as being of paramount importance for continuing professional competence, problem-based learning curricula, and adult learning theory, techniques for ensuring valid judgments have proven elusive. This study tested the applicability of an innovative relative-ranking procedure to problem-based learning tutorials. METHOD: A total of 36 students in the McMaster University Faculty of Health Sciences' MD program were provided relative-ranking forms listing seven domains of competence along with their definitions. The student, two of the student's peers, and the student's tutor were asked to complete the ranking exercise after their second, fourth, and sixth tutorials. RESULTS: Combining each level of the time and rater variables generated 66 correlation coefficients, none of which was significantly different from zero. Re-performing the analysis on only the extreme domains did not improve this result. CONCLUSION: The relative-ranking instrument developed did not prove to be a reliable measure of tutorial performance. Ratings were inconsistent from one week to the next as well as across raters within a week.