The stressor criterion in DSM-IV posttraumatic stress disorder: An empirical investigation

Background: The DSM-IV two-part definition of posttraumatic stress disorder (PTSD) widened the variety of stressors (Al) and added a subjective compon ent (A2). The effects of the revised stressor criterion on estimates Of exp osure and PTSD in a community sample are evaluated. Methods: A representative sample of 2181 persons in southeast Michigan were interviewed about lifetime history of traumatic events and PTSD. The evalu ation of the revised two-part definition is based on a randomly selected sa mple of events that represents the total pool of traumatic events experienc ed in the community. Results: The enlarged definition of stressors in A1 increased the total num ber of events that can be used to diagnose PTSD by 59%. The majority of A1 events (76.6%) involved the emotional response in A2. Females were more lik ely than males to endorse A2 (adjusted odds ratio = 2.66; 95% con fidence i nterval 1.92, 3.71). Of all PTSD cases resulting from the representative sa mple of events, 38% were attributable to the expansion of qualifying events in A1. The identification of exposures that lead to PTSD were not improved materially by A2; however, events that did not involve A2 rarely resulted in PTSD. Conclusions: Compared to previous definitions, the wider variety of stresso rs in A1 markedly increased the number of events experienced in the communi ty that can be used to diagnose PTSD. Furthermore, A2 might be useful as a separate criterion, an acute response necessary for the emergence of PTSD, and might serve as an early screen for identifying a subset of recently exp osed persons at virtually no risk for PTSD. The utility of A2 as a screen m ust be tested prospectively. (C) 2001 Society of Biological Psychiatry.