1. VA Greater Los Angeles Health Care System, Los Angeles, CA, USA
2. University of California Los Angeles, Los Angeles, CA, USA
3. VA Salt Lake City Health Care System, Salt Lake City, UT, USA
4. University of Utah School of Medicine, Salt Lake City, UT, USA
5. Birmingham VA Medical Center, Birmingham, AL, USA
6. University of Alabama at Birmingham School of Medicine, Birmingham, AL, USA
7. University of Alabama at Birmingham School of Public Health, Birmingham, AL, USA
8. VA Pittsburgh Healthcare System, Pittsburgh, PA, USA
9. University of Southern California, Los Angeles, CA, USA
10. University of Alabama at Birmingham College of Letters and Sciences, Birmingham, AL, USA