Dimensionality, reliability, and validity of the combat experiences scale.

Few studies have measured combat exposure during deployment to a war zone. Valid, reliable, and specific measurement is needed to broaden existing knowledge of combat experiences to accurately answer clinically important questions regarding postcombat treatment and recovery, particularly with the recognition of new kinds of combat and resulting psychological sequelae. The Combat Experiences Scale (CES) is a 33-item measure that assesses deployment-related experiences. The psychometrics of this measure, however, were undefined before this study. The purpose of this study was to examine aspects of internal and external validity of the CES. Data were collected as part of a study of 500 veterans of the conflicts in Iraq and Afghanistan across five Veterans Affairs medical centers in Upstate New York. An exploratory factor analysis suggested that three factors represented the scale well: Exposure to Combat Environment, Physical Engagement, and Proximity to Serious Injury and Death. The CES scores showed adequate internal consistency, and evidence for convergent validity and discriminant validity was also found. This study underscores the importance of casting a wide net with regard to the assessment of deployment-related experiences and provides evidence that probable post-traumatic stress disorder, depression, and anxiety are highly correlated with all forms of deployment-related experiences. Reprint &