This article on Post-Traumatic Stress Disorder (PTSD) discusses various risk factors for PTSD. From the article: "PTSD was originally conceptualized as a direct consequence of exposure to a traumatic event in otherwise normal individuals. As originally described, the emphasis was on establishing the primacy of the trauma as the etiologic agent, rather than individual vulnerability factors. Yet it was clear from the beginning that not all trauma survivors developed permanent disorder. In fact, many recovered. Thus, the search for risk factors that increase vulnerability to chronic PTSD occurred early in the history of the disorder. Foy et al. (1984) published one of the first formal studies to look at risk factors for PTSD and reported characteristics of trauma exposure to be of central importance. Numerous studies have since observed a dose-response relationship between trauma severity and PTSD. However, features of the trauma invariably account for a small proportion of the variance in PTSD symptoms (Yehuda & McFarlane, 1995). Epidemiological research has found the rate of exposure to trauma to far outweigh the prevalence of PTSD, indicating that most people do not ever develop PTSD following a traumatic event (Breslau et al., 1998). Moreover, PTSD is not the only possible psychological consequence of trauma. Elevated rates of major depression, panic, and substance abuse are commonly observed in traumatized populations (Shalev et al., 1998b), again calling into question the nature of the relationship between trauma and PTSD. Currently, some investigators are calling for PTSD to be recast in a stress-diathesis model, with trauma characteristics and individual risk factors interacting to determining who develops the disorder. The study of risk factors has become increasingly popular, emphasizing environmental and demographic factors, personality and psychiatric history, dissociation, cognitive and biological systems, and genetic or familial risk (Yehuda, 1999a). All of these approaches are essential in directing and advancing the field as a whole. To date, several important risk factors have been identified."
National Center for PTSD: http://www.ptsd.va.gov/
PTSD Research Quarterly (Summer 2000), v.11 no.3