Examining passage-related local item dependence (LID) and measurement construct using Q3 statistics in an EFL reading comprehension test

Abstract

The purpose of the study reported in this article is to empirically examine passage-related local item dependence (LID) by using an IRT (item response theory)- based LID index called Q3in an EFL reading comprehension test, with a special focus on item types as a potentially competing source of LID with passages. In this article, definitions and causes of LID and major LID detection methods including Q3statistics are reviewed along with the two potential sources of LID in EFL reading assessment. Scored item responses of 1857 Korean high school students to a 40-item EFL (English as a Foreign Language) reading comprehension test were analysed by using MULTILOG and IRTNEW. It was found that positive LID exists among items within passages, but no item-type-related LID was confirmed in the study. Subsequent content analysis of an item pair with an extreme Q3value has also provided some insights into the item characteristics that may exacerbate passage-related LID. These findings shed important light on the nature of passage-related LID, psychometric dimensionality, and measurement construct of the EFL reading comprehension test.