Trauma Exposure and Posttraumatic Stress Disorder in the Canadian Military

Objective: To estimate the lifetime prevalence of trauma exposure and posttraumatic stress disorder (PTSD) among a representative, active military sample, and to identify demographic and military variables that modulate rates of trauma exposure as well as PTSD rates and duration. Method: A cross-sectional weighted sample of 5155 regular members and 3957 reservists (n = 8441) of the Canadian Armed Forces (CAF) was face-to-face interviewed using a lay-administered structured interview that generates Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, psychiatric diagnoses. Results: Within this sample, 85.6% reported 1 or more trauma exposure, with a median number of 3 or more exposures. Compared with males, females were less likely (P < 0.05) to be exposed to warlike trauma (adjusted odds ratio [AOR] 0.40), disasters (AOR 0.43), assaultive violence (AOR 0.52), and witnessing trauma (AOR 0.75). However, they were more likely to report sexual assault (AOR 7.36). The lifetime prevalence of PTSD was 6.6% and the conditional rate was 7.7%. Both lifetime and conditional PTSD rates were higher among female soldiers, but lower among the reserve forces, both male and female. Finally, the median duration of PTSD was negatively influenced by younger age of onset, but not influenced by whether the event occurred during deployment. Conclusions: Active members of the CAF report a high degree of trauma exposure but a moderate rate of lifetime PTSD.