Trauma and conditional risk of posttraumatic stress disorder in two American Indian reservation communities.

Purpose: To determine conditional risk of posttraumatic stress disorder (PTSD) in two culturally distinct American Indian reservation communities.

Method: Data derived from the American Indian Service Utilization, Psychiatric Epidemiology, Risk and Protective Factors Project, a cross-sectional population-based survey that was completed between 1997 and 2000. This study focused on 1,967 participants meeting the DSM-IV criteria for trauma exposure.