Factor structure of PTSD in a community sample of sexual assault survivors

Recent factor analytic research on posttraumatic stress disorder (PTSD) has questioned the 3-factor structure of the diagnosis as codified in the Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV), proposing that a 4-factor model may more accurately reflect the phenomenology of the disorder. Confirmatory factor analyses of the Posttraumatic Stress Diagnostic Scale (E. B. Foa, 1995) were used to conduct model tests of the structure of PTSD in a large sample (N = 967) of adult female sexual assault survivors. A model specifying 4 correlated factors of reexperiencing, effortful avoidance, dysphoria, and hyperarousal provided the best fit to the data, although no model fits were excellent (including that of the traditional DSM-IV 3-factor model). Tests of measurement invariance across race and education suggest that differences may exist in the underlying factor structure of PTSD.