The effect of test item on reading comprehension: Difference between OPOI and OPMI

Abstract

Reading comprehension tests have played a critical role in many assessments of English language ability. Test items on a variety of English tests include one passage-one item (OPOI) principle to avoid the problem of local dependence. However, the effects of OPOI require more empirical investigation. This study examines the effects of OPOI compared to OPMI (One passage-multiple items) for an English reading comprehension test. The correlation between the OPOI score and a general English test as a criterion was compared with the correlation between the OPMI score and the same test. Two groups of students participated in this study: 76 high school seniors who had finished the 2020 CSAT and 94 sixth-grade elementary students. In the case of high school students, there was a stronger relationship between OPOI (.577) and the criterion test compared to OPMI (.403). Only the low- level students among the three groups of elementary students showed a higher correlation between the OPOI and the criterion test. Responses from a survey were also used to interpret the correlation results. The findings of this study imply that OPOI should be used more in school exams while it is advisable to use OPMI with caution to preclude local dependence.