1. Massachusetts Veterans Epidemiological Research and Information Center VA Boston Healthcare System Boston Massachusetts USA
2. Department of Psychiatry Boston University School of Medicine Boston Massachusetts USA
3. Department of Psychiatry University of Texas Health Science Center at San Antonio San Antonio Texas USA
4. Department of Psychiatry and Behavioral Sciences Duke University Medical Center Durham North Carolina USA
5. Department of Psychiatry, Perelman School of Medicine University of Pennsylvania Philadelphia Pennsylvania USA
6. Department of Epidemiology and Biostatistics University of Texas Health Science Center at San Antonio San Antonio Texas USA
7. Department of Behavioral Health Carl R. Darnall Army Medical Center Fort Hood Texas USA
8. Research and Development Service, South Texas Veterans Health Care System San Antonio Texas USA