Post-traumatic stress disorder (PTSD) - Statistics & FactsPost-traumatic stress disorder (PTSD) is a mental disorder that some people develop after experiencing or witnessing a traumatic event. Although PTSD is most often associated with war veterans and experiencing combat, it can develop in anyone that has been exposed to a traumatic event, such as a sexual assault, a natural disaster, or a serious injury. It is estimated that almost half of all rape victims will develop PTSD because of this traumatic experience, while 32 percent of those who have been physically assaulted or severely beaten may develop PTSD. PTSD does not only develop as a result of physical trauma but can also be caused by psychological trauma, with about 14 percent of those who experience an unexpected or sudden death of a friend or family member developing symptoms.