[1] Univ Calif Irvine, Dept Med, Div Gen Internal Med, Publ Hlth & Nursing,Informat Technol Enhancing Qu, Irvine, CA 92617 USA
[2] Univ Calif Los Angeles, David Geffen Sch Med, Borun Ctr, Los Angeles, CA 90095 USA
[3] Geriatr Res Educ & Clin Ctr, Vet Adm, Los Angeles, CA USA
[4] RAND, Santa Monica, CA USA
[5] Univ Calif Irvine, Dept Med, Div Gen Internal Med, iTEQC Res Program, Irvine, CA 92617 USA
[6] Univ Chicago, Dept Publ Hlth Sci, Chicago, IL USA