This study examined the life experiences of two American Indian reservation populations. The overall risk of PTSD, given trauma exposure, was comparable to that of other U.S. populations studied using similar methods. We conclude that greater prevalence of PTSD reported for these samples [16] compared to other Americans is largely due to higher rates of trauma exposure [6], not to differential rates of conditional PTSD across populations. The most remarkable difference, compared to other studies, is the relative muting of gender differences in conditional risk in these tribal samples. In contrast to the commonly observed pattern of higher rates of trauma exposure among males nationally, men and women in our sample were equally likely to report trauma exposure. Similarly, although data from both the NCS and the DAST found traumatized women more often developed PTSD than did traumatized men, our findings showed a less marked gender differential. This was especially true for interpersonal traumas.
