A cluster analysis of symptom patterns and adjustment in Vietnam combat veterans with chronic posttraumatic stress disorder.

This study investigated whether a subgroup of veterans with malignant posttraumatic stress syndrome, as described by Rosenheck (1985) and Lambert et al. (1996), could be identified via cluster analysis within two samples of Vietnam veterans with combat-related posttraumatic stress disorder (PTSD). In the initial subsample (n = 157), four clusters were identified, including a subgroup that scored consistently higher on measures of interpersonal violence and current physical problems.