Testing the Dimensionality of PTSD and the Specificity of the Dysphoria Factor

This study aimed to test the factor structure of Posttraumatic Stress Disorder (PTSD). The resultant PTSD factors were associated with different traumatic experiences. Based on previous factor analytic findings and the DSM-IV formulation, three confirmatory factor models were assessed. The best fitting model was re-fitted within a multiple causes multiple indicators model (MIMIC) which assessed associations between factors and trauma experiences. The sample consisted of 591 respondents from the National Comorbidity Survey who met the criteria for lifetime PTSD measured via a modified version of the Composite International Diagnostic Interview. A correlated four-factor model proposed by Simms et al. provided the best fit to the data. There were no significant associations with trauma experiences and the Dysphoria factor. This current study adds to the growing body of literature supporting a four-factor Dysphoria model. Additionally, this study adds to the literature suggesting that the Dysphoria factor is a non-specific component of PTSD.