[1] VA Puget Sound Hlth Care Syst, Seattle, WA 98108 USA
[2] Univ Washington, Dept Med, Seattle, WA 98195 USA
[3] VA Connecticut Hlth Care Syst, New Haven, CT USA
[4] Yale Univ Sch Med, New Haven, CT USA
[5] VA Salt Lake City Hlth Care Syst, Salt Lake City, UT USA
[6] Univ Utah, Sch Med, Salt Lake City, UT USA
[7] VA Greater Angeles Healthcare Syst, Los Angeles, CA USA
[8] UCLA, David Geffen Sch Med, Los Angeles, CA USA
[9] Atlanta VA Med Ctr, Atlanta, GA USA
[10] Univ Iowa Carver, Coll Med, Dept Med, Iowa City, IA USA
[11] Fac Epidemiol & Populat Hlth, London Sch Hyg & Trop Med, London, England
[12] Michael E DeBakey VA Med Ctr, Houston, TX USA
[13] Baylor Coll Med Houston, Houston, TX USA
[14] Yale Sch Publ Hlth, New Haven, CT USA