A preliminary study on the relationship between the length of A2 type objective test questions and the degree of difficulty and discriminative power in medical examination / 中华医学教育探索杂志

ABSTRACT

Objective In a large-scale clinical medical examination, A2 type best multiple-choice test questions to the same knowledge were used respectively in simple and complex form, to compare the difficulty and discrimination indices of the two forms of test questions and provide evidence to the improve-ment of clinical medical examination. Method In a large-scale clinical medical examination more than 4000 candidates participated, and 20 questions to different knowledge points were randomly selected and used in the examination respectively in simple and complex A2 type best multiple-choice test questions. The difficulty and discrimination indices of the two forms of test questions were compared. Results The average difficulty coefficient of the 20 simple test questions (65.5 words per question in average) is 0.6829, and the average discriminative powers are 0.2675 and 0.2579 respectively using identification index method and point biserial correlation method. The average difficulty coefficient of the 20 complex test ques-tions (135.5 words per question in average) is 0.7095, and the average discriminative powers are 0.3065 and 0.2967 respectively using identification index method and point biserial correlation method. Conclusion To the same knowledge points, the average difficulty of complex A2 type best multiple-choice test questions is slightly lower than the simple ones, while the average discriminative power is increased in the complex questions. The complex A2 type test questions are of higher quality and more in line with the requirements of the medical entrance examination, medical education and examination reform.