Adding guidance to deliberate reflection improves medical student's diagnostic accuracy.

There was a significant primary effect of experimental condition (P < .001), year of training (P < .001) and study phase (P < .001) on the diagnostic accuracy achieved. The use of deliberate reflection in addition to instructional guidelines resulted in improved results in the immediate test for all cases evaluated (P < .001), regardless of participants' seniority. In the delayed test, this benefit was maintained for simple cases (P < .001). For complex cases, the benefit was maintained only for senior students (P < .001). The cued reflection and worked example groups did not differ in performance (P > .05), but both groups surpassed the free reflection group (P < .001), regardless of the students' learning stage and case complexity.