SUMMARY
Attention to posttraumatic stress disorder (PTSD) in children has lagged behind the understanding of this disorder in adults. This article provides a brief review related to the stressor criterion of PTSD in children. The stressor criterion for PTSD includes three elements-an event, exposure, and a subjective reaction-each of which is described in the diagnostic criteria for the disorder. A host of stressors, both natural and human-caused, have the potential to evoke symptoms. Exposure can be direct-through, for example, physical presence, direct victimization, and witnessing, or indirect-through, for example, an interpersonal relationship with a direct victim. Exposure to media coverage of an event as a stressor for PTSD has also been examined. The requirement of a subjective reaction to the event is supported by research. A number of factors limit the ability to investigate issues associated with the stressor criterion including difficulty obtaining reliable and valid measures. Future studies should focus on specific aspects of exposure and outcomes, indirect forms of exposure, the clinical significance of findings, and the various factors that influence a child's reaction to trauma.