The aetiology of post-traumatic stress disorders following a natural disaster.

The onset of post-traumatic stress disorders in a group of firefighters who had an intense exposure to a bushfire disaster was investigated using a longitudinal research design. Contrary to expectation, the intensity of exposure, the perceived threat, and the losses sustained in the disaster, when considered independently, were not predictors of post-traumatic stress disorder. By contrast, introversion, neuroticism, and a past history and family history of psychiatric disorder were premorbid factors significantly associated with the development of chronic post-traumatic stress disorders.