Difficulty, discrimination and cognitive level of Microbiology exam questions of the Faculty of Medicine of Tunisia
Hermi, A.; Achour, W.
La Tunisie Medicale 93(8-9): 487-490
2015
ISSN/ISBN: 0041-4131 PMID: 26815509 Document Number: 681896
Based on difficulty and discrimination indices and cognitive levels of Bloom, we assessed in this study the quality of Microbiology exam questions (main session 2012-2013, Faculty of Medicine of Tunis). We analyzed 70 questions: 16 (exam"A") given to 533 students (1st year), 28 and 26 (exams"B1" and "B2") given respectively to 285 and 292 students (3rd year). For every question, we determined difficulty and discrimination indices and the highest cognitive level required to resolve it. We calculated mean difficulty and discrimination indices for each exam and cognitive level, and mean indices of discrimination for every difficulty degree. The 70 questions were of optimum difficulty (0.58), good discrimination (0.31) and explored mainly (58.57%) the lowest cognitive level. For both years, mean indices of difficulty were acceptable, while those of discrimination were good (0.33) and marginal (0.27) for respectively 3rd and 1st year. "A" explored Lower Orders of Cognitive Skills (LOCS), "B2" both Lower and High Orders and "B1" all orders. Mean difficulty indices of every cognitive level were acceptable except for the median one (0.83). Mean discrimination indices were good for all cognitive levels except for LOCS of the 1st year (0.27). Mean indices of discrimination were marginal (0.29) for difficult questions and good for others. Compared to B2, B1 was more attainable and discriminative, free of poor discrimination questions, and explored all cognitive orders. Our study remains specific to particular questions and generalizations seem difficult. However, it can serve as a guideline to other similar studies.