Military occupational designations are standardized classifications that help define and convey a service member's expected duties and responsibilities. The present study examined how occupational designation was related to adverse combat-reactions, specifically posttraumatic stress disorder (PTSD). It was hypothesized that at comparable levels of combat, non-combat units would display greater symptomology than combat units. The study sample consisted of 785 combat-deployed, active-duty enlisted US Army personnel. Participants were administered self-report questionnaires, including the Combat Experiences Scale and PTSD Checklist for DSM-5. Occupation was coded using the three-branch system (i.e., Operations, Support, & Force Sustainment). Hierarchical multiple linear regression (MLR) was run to examine the effect of occupation, combat, and unit cohesion on PTSD symptoms. Operations units reported the highest frequency of combat exposure; however, Force Sustainment units displayed the highest PTSD symptoms. In MLR analysis, there was a significant interaction between Force Sustainment units and combat exposure (= 0.10, = .019), that was not observed in Operations or Support units. These findings demonstrate that PTSD symptom intensity is not solely a function of combat exposure, and that non-combat units may react differently when exposed to elevated levels of combat.
