Aim: This study aims to assess the quality of the MCQ item analysis of dental students' final year orthodontics examination using the difficulty index (DIF I), discrimination index (DI), and distractor efficiency (DE) parameters. Additionally, the relationship between these parameters is determined to categorize the tested MCQs into either acceptable, which would be stored in the MCQ bank, or substandard (poor), which would be eliminated or rephrased.
Methods: Four MCQ examinations from the sixth-year undergraduate orthodontic course of the academic year 2018–2019 were evaluated by item analysis using the DIF I, DI, and DE. A total of 165 MCQ items (495 distractors) were collated and analyzed after 189 students answered the tests.
Results: The mean and standard deviation of the DIF I and DI were 0.76 (+0.19) and 0.25 (+0.14), respectively. Distraction assessments revealed that 27.5% were non-functional distractors (NFDs) with a DE of 78.2%. There was a significant negative correlation between the DIF I and the DI (r: -0.711; p < 0.01). A significant positive correlation was found between the DIF I and NFDs (r: 0.644; p < 0.01). Of the 165 MCQ items, 153 were considered sufficiently good to be stored in the MCQ bank, and only 12 were poorly constructed and recommended for elimination or rephrasing.
Conclusion: Item analysis was effective in identifying the good and poorly constructed MCQ items. Therefore, it should be used with each university MCQ examination for the development of a reliable and valid MCQ bank.