Examining the factor structure of the Acquired Capability for Suicide Scale (ACSS) in a military population: Initial development and validation of a four-factor version of the ACSS.

Suicide occurs at high rates in both military and veteran populations. The Interpersonal Theory of Suicide is a widely applied framework incorporating the requisite construct of acquired capability for suicide, which is the ability to engage in suicidal behaviors developed through painful and provocative life experiences. The Acquired Capability for Suicide Scale (ACSS) was developed to assess this construct. Despite substantial literature examining Interpersonal Theory of Suicide in military samples, many versions of ACSS have been used without adequate validation. The goal of this study was to examine the factor structure of the ACSS and derive a version of the ACSS with initial validity for use in military populations. We also examined the stability of acquired capability over time. Data were collected among Wisconsin Army National Guard service members, who were deployed to the Middle East from 2008 to 2010, at three assessment points: before deployment ( = 714), immediately after return from deployment ( = 2,553), and 6-9 months postdeployment ( = 646). Exploratory and confirmatory factor analyses of postdeployment data suggest adoption of a novel, abbreviated 15-item, four-factor version of the ACSS. Analyses provided preliminary support for discriminant and predictive validity. Results also revealed that acquired capability for suicide increases after deployment and remains stable for at least 6-9 months after return from the combat. The four-factor version of the ACSS shows promise as a theory-relevant and empirically supported instrument for research and clinical applications in the military population. (PsycInfo Database Record (c) 2025 APA, all rights reserved).