Introduction One-minute preceptor (OMP) and SNAPPS (a mnemonic for Summarize history and findings; Narrow the differential; Analyze the differential; Probe the preceptor about uncertainties; Plan management; and Select case-related issues for self-study) are educational techniques developed to promote learners’ expression of clinical reasoning during the case presentation in the workplace. The aim of this present study was to compare the content of the case presentation between the SNAPPS and the OMP methods.

Methods This was a randomized controlled trial comparing SNAPPS and OMP in 60 medical students at the beginning of their fifth year of medical school. After an introduction session, students presented and discussed two cases based on real patients and provided in written format. All case presentations were recorded and evaluated by two researchers. The assessed elements of the case presentations were divided into three subgroups related to expression of clinical reasoning, time and initiative to guide the presentation.

Results There were 30 participants in each group. There was no difference in the expression of clinical reasoning between OMP and SNAPPS groups (number of differential diagnoses, justification of most likely diagnosis and differential diagnosis, expression of comparing and contrasting hypotheses). However, students in the SNAPPS group expressed significantly more questions and uncertainties (p < 0.001), and more often took the initiative to present and justify the most likely diagnosis, differential diagnosis and management plan than students in the OMP group, both in simple and complex cases (all p values <0.001) without extending the length of the teaching session.