Scaffolding clinical reasoning of medical students with virtual patients: effects on diagnostic accuracy, efficiency, and errors.
Background Understanding clinical reasoning is a major challenge in medical education research. Little is known about the influence of scaffolding and feedback on the clinical reasoning of medical students. The aim of this study was to measure the effects of problem representation (cognitive representation of a clinical case) and structured scaffolding for reflection with or without feedback on the diagnostic efficiency and characterization of diagnostic errors of medical students. Methods One hundred and forty-eight advanced medical students were randomly assigned to one of five groups (2 × 2 design with a control group). They worked on 15 virtual clinical cases (five learning cases, five initial assessment cases, and five delayed assessment cases) in an electronic learning environment. After each case, they stated their presumed diagnosis and explained their diagnostic conclusion. Diagnostic accuracy, efficiency, and error distribution were analyzed. Results The diagnostic accuracy (number of correctly solved cases) and efficiency (solved cases/total time) did not differ significantly between any of the groups in the two different assessment phases [mean = 2.2-3.3 (standard deviation [SD] = 0.79-1.31), p = 0.08/0.27 and mean = 0.07-0.12 (SD = 0.04-0.08), p = 0.16/0.32, respectively]. The most important causes for diagnostic errors were a lack of diagnostic skills (20%), a lack of knowledge (18%), and premature closure (17%). Conclusions Neither structured reflections nor representation scaffolding improved diagnostic accuracy or efficiency of medical students compared to a control group when working with virtual patients.