[1] Kaiser Permanente Northwest, Ctr Hlth Res, 3800 N Interstate Ave, Portland, OR 97227 USA
[2] Kaiser Permanente, Med Care Program, Div Res, Oakland, CA USA
[3] Southern Arizona Vet Affairs Hlth Care Syst, Tucson, AZ USA
[4] Univ Arizona, Coll Med, Tucson, AZ USA
[5] City Hope Natl Med Ctr, Dept Populat Sci, Div Nursing Res & Educ, Duarte, CA USA