Association of Simulation Participation With Diagnostic Reasoning Scores in Preclinical Students.

PURPOSE The aim of the study was to evaluate for an association between the number of voluntary mannequin simulation sessions completed during the school year with scores on a year-end diagnostic reasoning assessment among second-year medical students. METHOD This is retrospective analysis of participation in 0 to 8 extracurricular mannequin simulation sessions on diagnostic reasoning assessed among 129 second-year medical students in an end-of-year evaluation. For the final skills assessment, 2 physicians measured students' ability to reason through a standardized case encounter using the Diagnostic Justification (DXJ) instrument (4 categories each scored 0-3 by raters reviewing students' postencounter written summaries). Rater scores were averaged for a total DXJ score (0-12). To provide additional baseline comparison, zero participation students were divided into 2 groups based on intent to participate: those who signed up for extracurricular sessions but never attended versus those who never expressed interest. Scores across the attendance groups were compared with an analysis of variance and trend analysis. RESULTS The class DXJ mean equaled 7.56, with a standard deviation of 2.78 and range of 0 to 12. Post hoc analysis after a significant analysis of variance (F = 4.91, df = 8, 128, P < 0.001) showed those participating in 1 or more extracurricular sessions had significantly higher DXJ scores than those not participating. Students doing 7 extracurricular sessions had significantly higher DXJ scores than those doing 0 and 2 (P < 0.05). Zero attendance groups were not different. A significant linear trend (R = 0.48, F = 38.0, df = 1, 127, P < 0.001) was found with 9 groups. A significant quadratic effect, like a dose-response pattern, was found (F = 18.1, df = 2, 125, P < 0.001) in an analysis including both zero attendance groups, a low (1-4 extracurricular sessions) group and a high (5-8) group. CONCLUSIONS Higher year-end diagnostic reasoning scores were associated with increased voluntary participation in extracurricular mannequin-based simulation exercises in an approximate dose-response pattern.