The NVVRS assessed the readjustment to civilian life and the prevalence of PTSD and other psychiatric disorders in 3016 Vietnam veterans 15-20 years after the war (Kulka et al. 1990). It was estimated that 15.2% of all male Vietnam-theater veterans had current (6-month) combat-related PTSD and 30.9% had lifetime combat-related PTSD (the former value is equivalent to about 479,000 of the 3.14 million men who served in the Vietnam theater). Of the 7200 female veterans, it was estimated that 8.5% had current PTSD and 26.9% had lifetime PTSD. The prevalence of current PTSD (35.8%) was 4 times as high in men (7 times as high as in women) exposed to high levels of war-zone stress as in men exposed to low or moderate war-zone stress (8.5%); 2-3 times as high as in those with service-connected physical disabilities (wounded in combat), and twice as high as in men (5 times as high in women) with lifetime substance-abuse disorders (Schlenger et al. 1992). Exposure to war-zone stress was more predictive of PTSD in the NVVRS study than were predisposing factors (Keane 1998).
Dohrenwend et al. (2006) reanalyzed the military records of 1200 male Vietnam-theater veterans from the NVVRS with a records-based military-history measure of exposure to war-zone stressors. Over 86% of the veterans with war-related PTSD described events that were personally life-threatening or involved witnessing death of or physical harm to others. A diagnosis of PTSD was based on the SCID. A dose-response relationship was established: fewer than 1% of low-exposed veterans had a diagnosis of current (as of 1988) war-related PTSD vs 28.1% of those in the high-exposure category. When adjusted for impairment of functioning and documentation of exposure to war-related traumatic events, the prevalence of lifetime and current war-related PTSD was 18.7% and 9.1%, respectively.
The Vietnam Experience Study (VES) was conducted by the Centers for Disease Control and Prevention in 1984 on a random sample of 2490 Vietnam theater and 1972 era Army veterans via telephone interview. A subsample of the respondents received a physical examination by a clinician and were interviewed with the DIS for assessment of psychiatric disorders (CDC 1988). Lifetime and current (1-month) PTSD rates were 14.7% and 2.2%, respectively, in the theater veterans 13 years after the end of the war. PTSD prevalence in the era veterans was not given. Using the same dataset, but including noncombat PTSD with combat-related PTSD, Boscarino (1995) found the prevalence of current PTSD in theater and era veterans to be 12% and 2%, respectively. PTSD was positively associated with reported combat exposure (OR 2.42, p < 0.001).
In an effort to reconcile the different prevalences of combat-related PTSD in Vietnam veterans reported in the NVVRS and the VES, Thompson et al. (2006) noted that the discrepancies could be minimized if the same definition of PTSD were applied to both studies. Rates determined with particularly broad and sensitive criteria were about 5 times those determined with more restrictive criteria. The authors concluded that consistent methods of diagnosis are needed to compare rates of PTSD in different studies of veteran populations.
O’Toole et al. (1996) found the prevalence of lifetime PTSD to be 21% in Australian Vietnam veterans (diagnosed with the SCID) and 12% for current PTSD, 20-25 years after the war.
Veterans of World War II and the Korean War who are participating in the Normative Aging Study, a long-term study established by the VA in Boston that has screened and tracked