[1] Kaiser Permanente Ctr Hlth Res, 3800 North Interstate Ave, Portland, OR 97227 USA
[2] City Hope Natl Med Ctr, Dept Nursing Res & Educ, 1500 E Duarte Rd, Duarte, CA 91010 USA
[3] Univ Arizona, Coll Med, Tucson, AZ USA
[4] Cpl Michael J Crescenz Vet Affairs Med Ctr, Philadelphia, PA USA
[5] Univ Penn, Perelman Sch Med, Philadelphia, PA 19104 USA