Mokken scale analysis of the Internet Gaming Disorder Scale-Short-Form and the Gaming Disorder Test

In recent years, research on disordered gaming has grown substantially with researchers developing different psychometric tools for assessing it. Two of the most prominent assessment tools are the Internet Gaming Disorder Scale-Short-Form (IGDS9-SF) and the Gaming Disorder Test (GDT), which evaluate disordered gaming under the American Psychiatric Association (APA) and the World Health Organization (WHO) frameworks, respectively. The main aim of this study was to assess and compare the scalability, reliability, and validity of both scales to determine if they effectively assess disordered gaming in a normative sample, through the Mokken Scale Analysis (MSA). A sample of 605 participants (42.31 % female, meanage = 23.98 years, SD = 9.21 years) was recruited for the present study. Results showed that both the IGDS9-SF and GDT were unidimensional, with all items presenting latent monotonicity fitting in the Monotone Homogeneity Model (MHM). Item characteristic curves did not intersect and presented with adequate fit in the Double Monotonicity Model (DMM). These findings further support the psychometric adequacy of the IGDS9-SF and GDT, attesting to their suitability to assess disordered gaming.

Assessing Cognitive Abilities Using the WAIS-IV: An Item Response Theory Approach

Background: The Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) has been adapted to 28 different cultures and there has been considerable interest in examining its structure through exploratory and confirmatory factor analysis. This study investigates item and scale properties of the Egyptian WAIS-IV using item response theory (IRT) models. Methods: The sample consisted of 250 adults from Egypt. The item-level and subtest statistical properties of the Egyptian WAIS-IV were established using a combination of four dichotomous IRT models and four polytomous IRT models. In addition, factor analysis was performed to investigate the dimensionality of each subtest. Results: Factor analysis indicated the unidimensionality of each subtest. Among IRT models, the two-parameter logistic model provided a good fit for dichotomous subtests, while the graded response model fitted the polytomous data. Most items of the Egyptian WAIS-IV showed high discrimination, and the scale was adequately informative across the levels of latent traits (i.e., cognitive variables). However, each subtest included at least some items with limited ability to distinguish between individuals with differing levels of the cognitive variable being measured. Furthermore, most subtests have items that do not follow the difficulty rank they are ascribed in the WAIS-IV manual. Conclusions: Overall, the results suggest that the Egyptian WAIS-IV offers a highly valid assessment of intellectual abilities, despite the need for some improvements.