Quality of multiple choice questions in undergraduate pharmacology assessments in a teaching hospital of Kerala, India: an item analysis

Abstract

Background: Carefully constructed, high quality multiple choice questions can serve as effective tools to improve standard of teaching. This item analysis was performed to find the difficulty index, discrimination index and number of non functional distractors in single best response type questions.Methods: 40 single best response type questions with four options, each carrying one mark for the correct response, was taken for item analysis. There was no negative marking. The maximum marks was 40. Based on the scores, the evaluated answer scripts were arranged with the highest score on top and the least score at the bottom. Only the upper third and lower third were included. The response to each item was entered in Microsoft excel 2010. Difficulty index, Discrimination index and number of non functional distractors per item were calculated.Results: 40 multiple choice questions and 120 distractors were analysed in this study. 72.5% items were good with a difficulty index between 30%-70%. 25% items were difficult and 2.5% items were easy. 27.5% items showed excellent discrimination between high scoring and low scoring students. One item had a negative discrimination index (-0.1). There were 9 items with non functional distractors.Conclusions: This study emphasises the need for improving the quality of multiple choice questions. Hence repeated evaluation by item analysis and modification of non functional distractors may be performed to enhance standard of teaching in Pharmacology.