The Dissociative Subtype of PTSD Scale: Initial Evaluation in a National Sample of Trauma-Exposed Veterans

Abstract

The fifth edition of the Diagnostic and Statistical Manual includes a dissociative subtype of posttraumatic stress disorder, but no existing measures specifically assess it. This article describes the initial evaluation of a 15-item self-report measure of the subtype called the Dissociative Subtype of Posttraumatic Stress Disorder Scale (DSPS) in an online survey of 697 trauma-exposed military veterans representative of the U.S. veteran population. Exploratory factor analyses of the lifetime DSPS items supported the intended structure of the measure consisting of three factors reflecting derealization/depersonalization, loss of awareness, and psychogenic amnesia. Consistent with prior research, latent profile analyses assigned 8.3% of the sample to a highly dissociative class distinguished by pronounced symptoms of derealization and depersonalization. Overall, results provide initial psychometric support for the lifetime DSPS scales; additional research in clinical and community samples is needed to further validate the measure.

Keywords: PTSD; dissociative subtype; latent profile analysis; psychometric.

Figures

Figure 1. Mean Severity Scores on PTSD and Dissociation by Latent Class

The figure shows the mean subscale severity on the National Stressful Events Survey (NSES) and the Dissociative Subtype of PTSD Scale (DSPS) as a function of latent class assignment. Each subscale severity score that was submitted to the analysis reflected the item means for the dichotomous items contributing to that subscale on the NSES and DSPS. PTSD = posttraumatic stress disorder; B = PTSD reexperiencing symptoms; C = PTSD avoidance symptoms; D = PTSD negative alterations in cognition and mood; E = arousal symptoms; dereal/depers = derealization/depersonalization; aware = awareness; psych = psychogenic. Means by class based on complete data (n = 688).