Introduction: Multiple choice questions (MCQs) offer high reliability and easy machine-marking, but allow for cueing and stimulate recognition-based learning. Very short answer questions (VSAQs) may circumvent these limitations. We investigated VSAQ reliability, discriminative capability, acceptability, and knowledge retention compared to MCQs. Methods: Dutch undergraduate medical students (n=375) were randomised to a formative exam with VSAQs first and MCQs second or vice versa in two courses, to determine reliability and discrimination. Next, acceptability (i.e., VSAQ review time) was determined in the summative exam. Knowledge retention at 2 and 5 months was determined by comparing score increase on the three-monthly progress test (PT) between students tested with VSAQs and students from previous years tested without VSAQs. Results: Reliability (Cronbachs alpha) was 0.74 for VSAQs and 0.57 for MCQs in one course. In the other course, Cronbachs alpha; was 0.87 for VSAQs and 0.83 for MCQs . Discrimination (Rir) was 0.27 vs. 0.17 and 0.43 vs. 0.39 for VSAQs vs. MCQs, respectively. Reviewing time of one VSAQ for the entire student cohort was ± 2 minutes on average. No clear effect on knowledge retention after 2 and 5 months was observed. Discussion: We found increased reliability and discrimination of VSAQs compared to MCQs. Reviewing time of VSAQs was acceptable. The association with knowledge retention was unclear in our study. This study supports and extends positive results of previous studies on VSAQs regarding reliability, discriminative capability, and acceptability in Dutch undergraduate medical students.

The authors have declared no competing interest.

This study did not receive any funding.

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Educational Research Review Board of the Leiden University Medical Centre gave ethical approval for this work.

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