Peritraumatic dissociation and experiential avoidance as prospective predictors of posttraumatic stress symptoms.

Peritraumatic dissociation (PD) and experiential avoidance (EA) have been implicated in the etiology of posttraumatic stress symptomatology (PTSS); however, the function of these two factors in the onset and maintenance of PTSS following a potentially traumatic event is unclear. The temporal relationships between EA, PD, and the four clusters of PTSS proposed by the Simms/Watson dysphoria model (Simms, Watson, & Doebbeling, 2002) were examined in a three-wave prospective investigation of 532 undergraduate women participating in an ongoing longitudinal study at the time of a campus shooting. Path analyses indicated that preshooting EA predicted greater PD, intrusions, and dysphoria symptoms approximately one month postshooting. PD was associated with increased symptomatology across all four clusters 1-month postshooting, while 1-month postshooting EA was associated with higher dysphoria and hyperarousal symptoms eight months postshooting. PD had a significant indirect effect on all four PTSS clusters eight months postshooting via 1-month postshooting symptom reports. The results suggest that both EA and PD show unique influences as risk factors for PTSS following a potentially traumatic event.