MMPI-2 based subgroups of veterans with combat-related PTSD: differential patterns of symptom change after treatment.

Considerable research has focused on the use of the MMPI to assess posttraumatic stress disorder (PTSD) through identification of mean profile configurations and the development of PTSD subscales. Little work, however, has addressed the heterogeneity of profiles evident in PTSD populations. This study investigated the MMPI-2 profiles of 158 Australian treatment-seeking Vietnam veterans with combat-related PTSD to identify distinct subgroups. Three robust subgroups were identified on the basis of their MMPI-2 profile and compared on PTSD and associated symptomatology. These subgroups consisted of a mild PTSD group with subclinical personality pathology, and two severe PTSD groups that differed in levels of personality disturbance and general psychopathology. Most notably, differences between these latter two groups occurred in the areas of externalization, alienation, and propensity for acting out. These groups were labeled as subclinical, trauma profile, and global. The groups demonstrated significant differences in the patterns of recovery after treatment. The subclinical group demonstrated little change after treatment. In contrast, the trauma profile and global groups both improved, although the trauma profile group demonstrated greater PTSD symptom reduction than the global group.