Fourth, the National Stressful Events Survey prevalence estimates of past year PTSD using the DSM-IV criteria were higher than those obtained in the National Comorbidity Survey-Replication (NCS-R; Kessler, Chiu, et al., 2005). Generally, patterns across sex were consistent with findings from the original NCS (Kessler et al., 1995) indicating similar magnitudes of elevated lifetime (Kessler, Berglund, et al., 2005) and past 12-month PTSD (Kessler, Chiu, et al., 2005) among women as compared to men. There are several potential reasons for the small DSM-IV PTSD prevalence difference across the two studies. The NCS-R is exemplary and used a sample drawn and weighted to be representative of the U.S. adult population in 2000. The NCS-R used an in-person assessment strategy with a highly structured interview to measure PTSD. The present National Stressful Events Survey sample was recruited from an online web panel, and our data were weighted to 2010 Census estimates of the U.S. adult population, which has different demographic characteristics than the 2000 Census (e.g., a higher proportion of Hispanics). These demographic changes in the U.S. population could account for some
