The Brazilian version of the Inventory of Depression and Anxiety Symptoms-Expanded Version: Internal structure, invariance by sex and race, and associations with pathological personality traits.

The Inventory of Depression and Anxiety Symptoms-Expanded version (IDAS-II) is one of the few tools designed to assess internalizing symptoms based on dimensional models. We conducted two studies, the first testing internal validity aspects of the IDAS-II and the second testing the external validity of the scales. In the first study we adapted the IDAS-II to Brazilian Portuguese and tested its internal structure, including a higher order factorial solution coherent with the internalizing spectrum, the stability of the factor structure, and its measurement invariance for sex and racial groups. Participants were 2,379 Brazilian adults. In the second study, we investigated the IDAS-II scales' associations with broad pathological personality traits in Brazilian ( N = 245) and North American ( N = 402) samples. The results of the first study indicated that the IDAS-II scales are grouped into three first-order factors (Distress, Obsessions/Fear, and Positive Mood), replicating Wester et al. (2022) and Petre et al. (2023). Our results also suggested the plausibility of an internalizing second-order factor for the IDAS-II Brazilian version. The multigroup confirmatory factor analysis shows that this scale is invariant for males and females and for White and Black/Brown people. In the second study, the IDAS-II scales demonstrated mostly coherent associations with broad domains of pathological personality traits. Besides the internal validity of the Brazilian IDAS-II, our results also provide information about its external validity and expand its nomological network, as it is the first study reporting its associations with broad domains of pathological personality traits. (PsycInfo Database Record (c) 2024 APA, all rights reserved).