Pearce K A, Schauer A H, Garfield N J, Ohlde C O, Patterson T W
J Clin Psychol. 1985 Jan;41(1):9-14. doi: 10.1002/1097-4679(198501)41:1<9::aid-jclp2270410103>3.0.co;2-1.
Three groups of Vietnam-era veterans were compared on the frequency of symptoms typical of the diagnostic criteria for Post Traumatic Stress Disorder (PTSD), a diagnostic category introduced in DSM III (N = 90). The three groups consisted of veterans who had experienced (a) a war-related traumatic event; (b) a non-war-related traumatic event; or (c) no traumatic event. The results indicated that the two groups who experienced a traumatic event reported significantly more symptoms than the group who never experienced a traumatic event. Furthermore, the group who experienced a war-related traumatic event reported more symptoms than the group who experienced a non-war-related traumatic event. These results support the validity of PTSD.