BACKGROUND Evidence is sparse about whether body weight categories in adolescents are associated with differences in pediatric HRQoL rated by adolescents and parents. Additionally, it is unknown whether HRQoL rated by individuals with different body mass index (BMI) weight categories is psychometrically comparable. This study aimed to assess whether difference in pediatric HRQoL rated by adoles...

The Medical Specialization Education Entrance Examination is a national high-stake test for the placement of medical graduates in specialization training Turkey. purpose this study to determine whether items display gender-related differential item functioning (DIF) by using Mantel-Haenszel and logistic regression methods. To presence bias, content experts reviewed items. analyzes were conducte...

Perceived self-efficacy (SE) for eating fruit and vegetables (FV) is a key variable mediating FV change in interventions. This study applies item response modeling (IRM) to a fruit, juice and vegetable self-efficacy questionnaire (FVSEQ) previously validated with classical test theory (CTT) procedures. The 24-item (five-point Likert scale) FVSEQ was administered to 1578 fourth graders from 26 H...

BACKGROUND This study aims at analyzing Health related quality of life (HRQoL) data on the French general population between 1995 and 2003 using an Item Response Theory (IRT) model. METHODS Data concerned 26388 individuals having responded to the SF36 questionnaire in 1995 or in 2003. General Health, Mental Health and Physical Functioning dimensions have been analyzed using a latent regressio...

of the Dissertation Identifying DIF for Latent Classes with the Dirichlet Process by Miles Satori Chen Doctor of Philosophy in Statistics University of California, Los Angeles, 2015 Professor Peter Bentler, Chair In Item Response Theory (IRT), Differential Item Functioning (DIF) occurs when individuals who have the same ability, but belong to different groups, have different probabilities of an...

Likert scales are routinely used in educational and psychological research as measures of constructs of interest. If sound scale development procedures are followed, the resulting scale can reliably and validly measure a construct. However, if a given scale is used to make comparisons among different populations of respondents (e.g., cultures; Riordan & Vandenberg, 1994), over time in longitudi...

Validation is an important enterprise especially when a test is a high stakes one. Demographic variables like gender and field of study can affect test results and interpretations. Differential Item Functioning (DIF) is a way to make sure that a test does not favor one group of test takers over the others. This study investigated DIF in terms of gender in the reading comprehension subtest (35 i...

The Center for Epidemiological Studies-Depression (CES-D) scale is a widely used measure of depressive symptoms, but its psychometric properties have not been adequately evaluated among adults with HIV/AIDS. This study used an item response theory approach (Rasch analysis) to evaluate the CES-D's validity and reliability in relation to key demographic and clinical variables in adults with HIV/A...

In this paper we describe and illustrate the Roussos-Stout (1996) multidimensionality-based DIF analysis framework, with emphasis on its implication for the selection of a matching and studied subtest for DIF analyses. Standard DIF practice encourages an exploratory search for matching subtest items based on purely statistical criteria, such as a failure to display DIF. By contrast, the multidi...