1. Atlanta VA Medical Center, Decatur, Georgia, USA;
2. Department of Psychiatry and Behavioral Sciences, Emory University, Atlanta, GA, USA;
3. VA Boston Healthcare System, Boston, Massachusetts, USA;
4. Department of Psychiatry, Boston University, Boston, Massachusetts, USA;
5. VA Puget Sound Health Care System, Seattle, Washington, USA;
6. Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington, USA