Item Analysis of Multiple Choice Questions at the Department of Paediatrics, Arabian Gulf University, Manama, Bahrain

Abstract

Objectives

The current study aimed to carry out a post-validation item analysis of multiple choice questions (MCQs) in medical examinations in order to evaluate correlations between item difficulty, item discrimination and distraction effectiveness so as to determine whether questions should be included, modified or discarded. In addition, the optimal number of options per MCQ was analysed.

Methods

This cross-sectional study was performed in the Department of Paediatrics, Arabian Gulf University, Manama, Bahrain. A total of 800 MCQs and 4,000 distractors were analysed between November 2013 and June 2016.

Results

The mean difficulty index ranged from 36.70–73.14%. The mean discrimination index ranged from 0.20–0.34. The mean distractor efficiency ranged from 66.50–90.00%. Of the items, 48.4%, 35.3%, 11.4%, 3.9% and 1.1% had zero, one, two, three and four nonfunctional distractors (NFDs), respectively. Using three or four rather than five options in each MCQ resulted in 95% or 83.6% of items having zero NFDs, respectively. The distractor efficiency was 91.87%, 85.83% and 64.13% for difficult, acceptable and easy items, respectively ( P <0.005). Distractor efficiency was 83.33%, 83.24% and 77.56% for items with excellent, acceptable and poor discrimination, respectively ( P <0.005). The average Kuder-Richardson formula 20 reliability coefficient was 0.76.

Conclusion

A considerable number of the MCQ items were within acceptable ranges. However, some items needed to be discarded or revised. Using three or four rather than five options in MCQs is recommended to reduce the number of NFDs and improve the overall quality of the examination.