The generalizability aspect of Construct validity, as proposed by Messick (1989), requires that a test measures the same trait across different samples from the same population. Differential Item functioning (DIF) analysis is a key component in the fairness evaluation of educational tests. University entrance exam for the candidates who seek admission into master's English programs (MEUEE) at I...

the university of tehran english proficiency test (utept) is a high-stakes entrance examination taken by more than 10,000 master’s degree holders annually. the examinees’ scores have a significant influence on the final decisions concerning admission to the university of tehran ph.d. programs. as a test validation investigation, the present study, which is a bias detection research in nature, u...

Background During the past few decades, there have been many studies conducted to evaluate the comparative performance of differential item functioning (DIF) methods under various conditions. These conditions, for example, include small and unbalanced sample size between groups (Woods 2009), short tests (Paek and Wilson 2011), various levels of DIF contamination (Finch 2005), multilevel data (F...

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...

INTRODUCTION We present an ordinal logistic regression model for identification of items with differential item functioning (DIF) and apply this model to a Mini-Mental State Examination (MMSE) dataset. We employ item response theory ability estimation in our models. Three nested ordinal logistic regression models are applied to each item. Model testing begins with examination of the statistical...

BACKGROUND This study aimed to evaluate the psychometric properties of four self-efficacy scales (i.e., self-efficacy for fruit (FSE), vegetable (VSE), and water (WSE) intakes, and physical activity (PASE)) and to investigate their differences in item functioning across sex, age, and body weight status groups using item response modeling (IRM) and differential item functioning (DIF). METHODS ...

To examine differences in the psychometric characteristics of diagnostic criteria for Substance Use Disorders (SUD) between substance users harm reduction settings (HR) and seeking treatment (Tx). Differential Item Test Functioning (DIF & DTF) analysis were performed to difficulty endorsement discrimination 11 test if set as a whole (the “test”) functioned differently by care (Tx vs. HR) alcoho...