Item analysis of multiple-choice questions in summative assessment for professional examination I of an outcome-based integrated MBBS curriculum

Background: This study presents an item analysis of multiple-choice questions (MCQ-Type A) used in the summative assessment for Professional Examination I at Defence Services Medical Academy, Yangon, Myanmar. The objectives of the study were to perform item analysis using Difficulty Index (DIF I) and Discrimination Index (DI) and to correlate between DIF I and DI. Methods: A cross-sectional observational study was conducted with 200 multiple-choice questions from two written examination papers answered by 46 medical year 2 students of Defence Services Medical Academy, Yangon, Myanmar. Item analysis of multiple-choice questions were done by using DIF I and DI calculated post-exam. Results: Results showed that the majority of items were categorized as easy based on DIF I, with 63% and 60% in Papers I and II, respectively. Only about one-third of items were deemed acceptable, and few fell into the difficult category. DI ranged from negative to excellent, with 62% and 61% of MCQs in Papers I and II showing acceptable to excellent discrimination. Items with poor discrimination (35% and 34% in Papers I and II) should be revised or discarded. Moreover, items with negative DI should be re-evaluated for potential key errors or vague wording. A low negative correlation between DIF I and DI was observed, indicating that as DIF I increased, discrimination power decreased. Notably, items with easy DIF I demonstrated a moderate negative correlation with DI, consistent with previous research. Conclusions: This study underscores the importance of item analysis to enhance the validity of assessment tools and ensure the effective evaluation of student cognition levels. Consequently, reconstruction and modification of MCQs are recommended to improve assessment quality and accurately measure student abilities.