1. U.S. Department of Veterans Affairs, Atlanta VA Health Care System, Decatur, GA, USA
2. Emory University School of Medicine, Atlanta, GA, USA
3. U.S. Department of Veterans Affairs, San Francisco VA Health Care System, San Francisco, CA, USA
4. University of California, San Francisco, CA, USA
5. U.S. Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, TN, USA
6. Emory University Nell Hodgson Woodruff School of Nursing, Atlanta, GA, USA
7. US Department of Veterans Affairs, Michael E. Debakey VA Medical Center, Houston, TX, USA
8. Baylor College of Medicine, Houston, TX, USA