1. National Center for PTSD VA Boston Healthcare System Boston Massachusetts USA
2. Department of Psychiatry Boston University School of Medicine Boston Massachusetts USA
3. Department of Epidemiology Boston University School of Public Health Boston Massachusetts USA
4. Department of Clinical Epidemiology Aarhus University Hospital Aarhus Denmark
5. Center for Anxiety and Related Disorders Department of Psychological and Brain Sciences Boston University Boston Massachusetts USA
6. Department of Epidemiology Rollins School of Public Health Emory University Atlanta Georgia USA