The purpose of this study is to help ensure that strategies for differential item functioning (DIF) detection for students with disabilities are appropriate and lead to meaningful results. We surveyed existing DIF studies for students with disabilities and describe them in terms of study design, statistical approach, sample characteristics, and…

The nature of the matching criterion (usually the total score) in the study of differential item functioning (DIF) has been shown to impact the accuracy of different DIF detection procedures. One of the topics related to the nature of the matching criterion is whether the studied item should be included. Although many studies exist that suggest…

Extreme linkings are performed in settings in which neither equivalent groups nor anchor material is available to link scores on two assessments. Examples of extreme linkages include links between scores on tests administered in different languages or between scores on tests administered across disability groups. The strength of interpretation…

Santelices and Wilson (2010) claimed to have addressed technical criticisms of Freedle (2003) presented in Dorans (2004a) and elsewhere. Santelices and Wilson's abstract claimed that their study confirmed that SAT[R] verbal items do function differently for African American and White subgroups. In this commentary, I demonstrate that the…

CBAL, an acronym for Cognitively Based Assessment of, for, and as Learning, is a research initiative intended to create a model for an innovative K-12 assessment system that provides summative information for policy makers, as well as formative information for classroom instructional purposes. This paper summarizes empirical results from 16 CBAL…

This study compared the accuracies of four differential item functioning (DIF) estimation methods, where each method makes use of only one of the following: raw data, logistic regression, loglinear models, or kernel smoothing. The major focus was on the estimation strategies' potential for estimating score-level, conditional DIF. A secondary focus…

There has been an increased interest in developing computer-adaptive testing (CAT) and multistage assessments for K-12 accountability assessments. The move to adaptive testing has been met with some resistance by those in the field of special education who express concern about routing of students with divergent profiles (e.g., some students with…

To ensure fairness, it is important to better understand the relationship of language proficiency with the standard procedures of psychometric analysis. This paper examines how equating results are affected by an increase in the proportion of examinees who report that English is not their first language, using the analysis samples for a…

In this research investigation of score comparability for language minority students (English language learners [ELLs] and former English language learners), we examined 3 indicators of score comparability (reliability, internal test structure, and differential item functioning) for 4th and 8th grade students who took the NCLB-mandated content…

To ensure fairness, it is important to better understand the relationship of language proficiency to standard psychometric analysis procedures. This paper examines how results of differential item functioning (DIF) analysis are affected by an increase in the proportion of examinees who report that English is not their first language in the…

The equating process links scores from different editions of the same test. For testing programs that build nearly parallel forms to the same explicit content and statistical specifications and administer forms under the same conditions, the linkings between the forms are expected to be equatings. Score equity assessment (SEA) provides a useful…

Research studies have shown that a smaller percentage of students with learning disabilities participate in state assessments than do their peers without learning disabilities. Furthermore, there is almost always a performance gap between these groups of students on these assessments. It is important to evaluate whether a performance gap on a…

The TOEFL iBT[TM] has increased the length of the reading passages in the reading section compared to the passages on the TOEFL[R] computer-based test (CBT) to better approximate academic reading in North American universities, resulting in a reduced number of passages in the reading test. A concern arising from this change is whether the decrease…