FIGURE 2. Weighted prevalence of lifetime and current PTSD by combat exposure and age cohort.
a PTSD defined according to DSM-tV criteria denved from the CID1-IV.
b Test statisticsfor combat exposure with lifetime PTSD prevalence: t(274) = 4.18, p < 0.001 for <60 age and t(1834) = 7.34, p < 0.001 for ≥60 age; combat by age cohort interaction t(2108) = 0.17, p = 0.86. Test statisticsfor combat exposure with current PTSD prevalence: t(273) = 3.60, p < 0.001 for <60 age and t(1831) = 6.92 p < 0.001 for ≥60 age; combat by age cohort interaction t(2104) = 0.47, p = 0.64.
c Prevalence is estimated from theater service Veterans with valid responses. Error bars represent 95% confidence intervals that account for clustering by twin pairs Weighted for non-response and to the characteristics of the living male US population of Vietnam-theater Veterans.