Item analysis of pharmacology multiple-choice questions used in the semester-I examination for second-year undergraduate medical students at Khesar Gyalpo University of Medical Sciences, Bhutan: a cross-sectional study

Abstract

ABSTRACT

Background: As the Faculty of Undergraduate Medicine is a newly established medical school in Bhutan, evaluation of the quality of assessment tools is essential. This study aimed to evaluate the quality of Pharmacology MCQs used in semester end summative examinations. Methods: MCQs used in the Semester I summative examination conducted in June 2025 for second-year MBBS students were analysed. A total of 50 MCQs were included in the study. Item analysis of 50 MCQs from the Semester-I Pharmacology examination administered to 24 second-year MBBS students was performed using difficulty index, discrimination index, distractor effectiveness, and Cronbach's alpha reliability analysis. An ethical waiver was obtained from the Institutional Review Board of the University. Statistical analysis was carried out using SPSS version 26. Results: Item analysis of the 50 MCQs showed that 60% of items had an acceptable (moderate) difficulty index, while 24% were categorized as very difficult and 16% as easy. Regarding the discrimination index, 64% of items demonstrated good to excellent discrimination, 20% showed fair discrimination, and 16% exhibited poor discrimination. Distractor analysis revealed that 67% of items had no non functioning distractors, although a small proportion (3%) contained three or more non-functioning distractors. Reliability analysis demonstrated acceptable internal consistency, with a Cronbach’s alpha value of 0.78 for the overall assessment. Conclusion: The majority of Pharmacology MCQs demonstrated acceptable difficulty and discrimination, with a Cronbach's alpha of 0.78. 
A proportion of items require revision, and routine item analysis is recommended as standard practice in summative assessment quality assurance.