A psychometric evaluation of the Inventory of Altered Self-Capacities in a trauma-exposed university sample: A replication and extension.

Abstract

The Inventory of Altered Self-Capacities (IASC; Briere, 2000) assesses difficulties in relatedness, identity, and affect regulation, which may help characterize complex posttraumatic stress disorder clinical presentations. There have been few psychometric studies of the IASC since its initial validation. We utilized a trauma-exposed university sample (n = 683) to (a) replicate the initial evaluation of the IASC's internal consistency and convergent and discriminant validity and (b) extend previous findings by evaluating the IASC's structural validity. Results indicated evidence of high internal consistency and convergent and discriminant validity of observed scores, but high levels of latent factor overlap. Confirmatory factor analysis and exploratory structural equation modeling results revealed an inadequate model fit for the IASC, highlighting factor differentiation concerns and a lack of support for the hypothesized factor structure. Findings suggest the IASC may provide clinically useful information for trauma-exposed populations but may need refinement of item and factor content to be psychometrically sound.