This study examined group differences in online reading comprehension (ORC) using student data from the 2016 administration of the Progress in International Reading Literacy Study (ePIRLS). An explanatory item response modeling approach was used to explore the effects of item properties (i.e., item format, text complexity, and cognitive…

In this study, we illustrated an application of the confirmatory mixture IRT model for multidimensional tests. We aimed to examine the differences in student performance by domains with a confirmatory mixture IRT modeling approach. A three-dimensional and three-class model was analyzed by assuming content domains as dimensions and cognitive…

Modern large-scale studies such as the Progress in International Reading Literacy Study (PIRLS) do not only report reading competence of students on a global reading scale but also report reading on the level of reading subskills. However, the number of and the dependencies between the subskills are frequently discussed. In this study, different…

Differential item functioning (DIF) assessment is key in score validation. When DIF is present scores may not accurately reflect the construct of interest for some groups of examinees, leading to incorrect conclusions from the scores. Given rising immigration, and the increased reliance of educational policymakers on cross-national assessments…

Out-of-level testing refers to the practice of assessing a student with a test that is intended for students at a higher or lower grade level. Although the appropriateness of out-of-level testing for accountability purposes has been questioned by educators and policymakers, incorporating out-of-level items in formative assessments for accurate…

The purpose of this study was to explore what may be contributing to differences in performance in mathematics on the Trends in International Mathematics and Science Study 2007. This was done by using a mixture item response theory modeling approach to first detect latent classes in the data and then to examine differences in performance on items…

In this study, we contrast results from two differential item functioning (DIF) approaches (manifest and latent class) by the number of items and sources of items identified as DIF using data from an international reading assessment. The latter approach yielded three latent classes, presenting evidence of heterogeneity in examinee response…

This study investigated whether the linguistic complexity of items leads to gender differential item functioning (DIF) on mathematics assessments. Two forms of a mathematics test were developed. The first form consisted of algebra items based on mathematical expressions, terms, and equations. In the second form, the same items were written as word…

This tutorial addresses possible sources of confusion in interpreting trait scores from the bifactor model. The bifactor model may be used when subscores are desired, either for formative feedback on an achievement test or for theoretically different constructs on a psychological test. The bifactor model is often chosen because it requires fewer…

Considerable research about standard setting has revolved around a U.S.-centric policy context. That is, over the past decade, conclusions about thought processes and the interaction of education policy and panelists' judgments have been based on assumptions of comparable policy settings. However, whether these assumptions generalize to other…

Studies of international mathematics achievement such as the Trends in Mathematics and Science Study (TIMSS) have employed classical test theory and item response theory to rank individuals within a latent ability continuum. Although these approaches have provided insights into comparisons between countries, they have yet to examine how specific…