Determination of Difficulty Index in End of Block Examinations of Preclinical Undergraduate Medical Students

Background: Multiple Choice Questions (MCQs) are considered a good choice for undergraduate formative assessment as they have higher reliability and are generally feasible. The objective of this study was to evaluate the difficulty index of Multiple-Choice Questions in the end of block examination of preclinical undergraduate medical students at Rawalpindi Medical University. Methodology: This descriptive cross-sectional study was conducted at Rawalpindi Medical University. End of Block assessment data was collected from Department of Medical Education, RMU. A total of 60 MCQs scores were randomly selected and the difficulty index was calculated after entering data in MS Excel. Data was then entered in SPSS version 24. Means and standard deviations of Difficulty indices were calculated and compared between first-year and second-year students by independent samples students t-test and between subjects by ANOVA. Results: Out of 120 Multiple Choice Items analyzed, in the first year MBBS block exam, 30% were easy, 65% were acceptable and 5% were difficult. In the second year MBBS block exam, 36.67% were easy, 56.67% were acceptable and 6.67% were difficult. There was no significant difference (p=0.986) between the mean difficulty index of first-year MBBS students and second-year MBBS students. However, the mean difficulty index was highest in physiology (66.53 ± 16.262) followed by biochemistry (64.36 ± 16.756) and anatomy (54.80 ± 17.665), and the mean difference between the subjects was statistically significant (p=0.005). The mean difficulty index in first-year MBBS students was highest for Biochemistry followed by Physiology and Anatomy. In second-year MBBS students, the mean difficulty index was highest in Physiology followed by Biochemistry and Anatomy. Conclusion: The difficulty index of Anatomy MCQs was lower indicating that the students find them more difficult than the other two subjects i.e., Physiology and Biochemistry in the first two years of their undergraduate medical studies.