Examining the dimensionality of combat-related posttraumatic stress and depressive symptoms in treatment-seeking OEF/OIF/OND veterans

Background: This study examined the factor structure of two of the most commonly used screening measures of posttraumatic stress disorder and depression in 164 treatment-seeking veterans who served in Operations Enduring Freedom/Iraqi Freedom/New Dawn (OEF/OIF/OND). Methods: Exploratory factor analysis was used to assess the dimensionality of items from the Posttraumatic Stress Disorder Checklist-Military Version (PCL-M) and the Patient Health Questionnaire-9 (PHQ-9). Regression analyses were then conducted to examine associations between factor scores of the resulting factor solution and measures of alcohol use, cognitive coping, psychological resilience, social support, and healthcare utilization. Results: A four-factor solution was found that consisted of clusters of symptoms reflecting reexperiencing/avoidance, detachment/numbing, hopelessness/depression, and bodily disturbance. Scores on the detachment/numbing factor were uniquely related to alcohol use, whereas scores on the hopelessness/depression factor was uniquely associated with emergency room visits. Compared to conventional PCL-M and PHQ-9 total scores, the four-factor solution explained 2 to 10% more variance in scores on measures of alcohol use, cognitive coping, psychological resilience, social support, and healthcare utilization. Limitations: This study was limited by a small sample size and cross-sectional design. Conclusions: Combat-related posttraumatic stress disorder and depressive symptoms in treatment-seeking OEF/OIF/OND veterans may be better conceptualized by four dimensions of reexperiencing/ avoidance, detachment/numbing, hopelessness/depression, and bodily disturbance symptoms. This symptom structure may provide greater utility when examining other outcomes of interest in this population.