Case-based workshop improves medical students’ diagnostic thinking in small randomized trial

A six-hour case-based clinical reasoning workshop was associated with statistically significant improvements in two measures of diagnostic thinking among fourth-year medical students in a small randomized controlled educational trial at Shiraz University of Medical Sciences. The workshop group improved more than the standard-curriculum group in flexibility of thinking and memory structure, while the difference between groups on a case-specific differential diagnosis test was not statistically significant.

The trial enrolled 51 fourth-year medical students completing internal medicine rotations. Eligible students had no prior formal training in clinical reasoning and were excluded if they had extensive previous clinical experience or had attended similar workshops. Computer-generated simple randomization allocated 26 students to the workshop and 25 to the control group. The groups had comparable baseline characteristics and pretest scores for age, gender distribution, diagnostic thinking and differential diagnosis performance.

Students in the intervention group received a six-hour workshop based on the book Principles and Practice of Case-Based Clinical Reasoning. The session covered principles of clinical reasoning and used a case of a patient presenting with headache. Participants identified key findings, generated initial differential diagnoses, prioritized hypotheses and revised their reasoning as additional information became available. They also discussed features that distinguished among potential diagnoses and considered how history, physical examination findings and laboratory data affected diagnostic decisions. Small-group discussions allowed students to apply and compare their reasoning pathways. Control students continued their regular internal medicine courses, including lectures and other didactic teaching, without additional clinical reasoning training.

The primary outcome was the Diagnostic Thinking Inventory, a self-report instrument measuring cognitive dispositions associated with diagnostic decision-making rather than direct clinical performance. Its two assessed domains were flexibility of thinking, which reflects consideration of alternative diagnoses and adaptation despite conflicting information, and structure of memory, which reflects the accessibility and organization of stored information during diagnostic tasks. Participants completed the inventory and a customized 10-question differential diagnosis examination before and after the intervention or corresponding study period.

Thinking flexibility increased in the intervention group from a mean of 74.35, with a standard deviation of 6.68, before the workshop to 76.88, with a standard deviation of 7.35, afterward. The control group changed only slightly, from 71.64, with a standard deviation of 7.95, to 71.28, with a standard deviation of 7.97. The improvement within the intervention group was statistically significant, with p=0.005, and the difference in change between groups was also significant, with p=0.002. Cohen’s d for the difference in improvement was 0.92, categorized by the researchers as a large effect.

Memory structure scores rose from a mean of 68.35, with a standard deviation of 8.32, to 70.69, with a standard deviation of 7.45, in the intervention group. In the control group, the mean increased from 65.68, with a standard deviation of 7.37, to 66.60, with a standard deviation of 6.44. The within-group improvement for workshop students was significant at p<0.001, and the between-group difference in change was significant at p=0.035. The reported Cohen’s d of 0.61 was categorized as a medium effect.

Both groups improved on the customized differential diagnosis test, but their gains did not differ significantly between groups, with p=0.409 for the difference in change. The effect size for that measure was Cohen’s d=0.22, categorized as small. Because the test was developed locally and contained only 10 items, formal reliability indices were not calculated. Its content and face validity were supported through expert review by internal medicine faculty and medical educators. The authors noted that this case-specific assessment may have been influenced by knowledge factors and may not have captured general diagnostic thinking in the same way as the self-report inventory.

These results concern diagnostic thinking among 51 students at one Iranian medical university, rather than patient outcomes or clinical performance. Several limitations constrain the findings: the sample was small and drawn from a convenience pool at a single institution; simple randomization was not stratified or blocked; participants and assessors were not blinded; the study was not registered; and identical pretest and posttest measures could have introduced familiarity or sensitization effects. The intervention was brief, evaluation was short-term and no follow-up assessed whether improvements persisted. The control group received standard teaching rather than another active instructional approach, limiting conclusions about the workshop’s specific effects relative to alternative educational strategies.

The trial provides evidence that a short case-based workshop can accompany improvements in selected general diagnostic-thinking dispositions among undergraduate medical students. It does not establish that such workshops improve case-specific differential diagnosis performance, because the between-group difference on that outcome was not statistically significant. The authors characterized the results as hypothesis-generating and called for larger, multi-institutional studies, longer follow-up, formal psychometric evaluation and active-comparator designs to clarify the educational value of case-based clinical reasoning instruction.

Subject of Research: Randomized educational trial testing a case-based clinical reasoning workshop for fourth-year medical students.

Article Title: Assessing the efficacy of a case-based clinical reasoning workshop for medical students: a randomized controlled trial

Article References: Golchin Vafa, R., Hasani, A. M., & Amini, M. (2026). Assessing the efficacy of a case-based clinical reasoning workshop for medical students: a randomized controlled trial. Discover Education, 5(1), Article 944. https://doi.org/10.1007/s44217-026-02171-9

Image Credits: AI Generated

DOI: 10.1007/s44217-026-02171-9

Keywords: medical education, clinical reasoning, case-based learning, medical students, randomized trial, diagnostic thinking, differential diagnosis, workshop, Shiraz University, Assessing, efficacy, case-based