Duration of Exposure and the Dose-Response Model of PTSD

A dose-response model underlies posttraumatic stress disorder (PTSD) and posits a relationship between event magnitude and clinical outcome. The present study examines whether one index of event magnitude-duration of exposure-contributes to risk of PTSD among female victims of sexual assault. Findings support a small but significant contribution of event duration to clinical status in the immediate aftermath of trauma but not at 3-month follow-up. The opposite pattern is obtained for subjective appraisals of threat. These findings add to a growing literature that suggests that a simple application of the dose-response model to objective event characteristics may be insufficient to explain the risk of PTSD.