[1] Vet Affairs Portland Hlth Care Syst, Hlth Serv Res & Dev, Portland, OR USA
[2] Vet Affairs Portland Hlth Care Syst, Sect Pulm & Crit Care Med, Portland, OR USA
[3] Oregon Hlth & Sci Univ, Dept Med, Div Pulm & Crit Care Med, 3181 SW Sam Jackson Pk Rd, Portland, OR 97239 USA
[4] Oregon Hlth & Sci Univ, Dept Psychiat, Div Geriatr Psychiat, Portland, OR 97239 USA
[5] Oregon Hlth & Sci Univ, Dept Med Informat & Clin Epidemiol, Portland, OR 97239 USA
[6] Edith Nourse Rogers Mem Vet Hosp, Ctr Healthcare Org & Implementat Res, Bedford, MA USA
[7] Boston Univ, Sch Med, Pulm Ctr, Boston, MA 02118 USA