The Relationship of Difficulty and Discrimination Indices with Physiology Teaching and Learning

Abstract

Background: Item analysis, a valuable process conducted after the examination, gives information regarding the reliability of scores and validity of items tested. Difficulty index (P) and Discrimination index (DI) are two parameters, which aid in analyzing the standard of Multiple Choice Questions (MCQs). The study was aimed to find the relationship of difficulty and discrimination indices with teaching and learning in Physiology.

Methods: Students (n=100) included were MBBS 1^st year from September 2017 to March 2018. The MCQs of Physiology semester II courses were analyzed in two Continuous Assessment Tests (CATs). CAT I included Respiratory: 15/50 and CAT II Hemopoietic: 14/60 and Semester Exam 40/80. The items were examined for difficulty index (p-value) and discrimination index (DI). Items having p-value between 0.3 to 0.7 and DI > 0.2 were considered as having good difficulty and discrimination indices respectively.

Results: Out of 15 items in Respiratory CAT, 73% had a mean p=0.3 -0.7 and 27% had mean p= 0.23. The mean DI value was 0.31. Out of 14 items in CAT of Hemopoietic, 85% had a p-value between 0.3 -0.7 and 15% had mean p=0.2. The mean DI value was 0.41. Out of 40 items in Semester exam, 82% items had p value b/w 0.3 – 0.7 and 18 % items had mean p=0.18. Overall mean DI value was 0.28.

Conclusion: The item analysis of majority of one best type MCQs of CATs and semester exam in Physiology had good difficulty and discrimination indices and matched teaching and learning strategy in Physiology.

Keywords: Difficulty Index; Discrimination Index; Physiology; Teaching; Learning.