[1] Univ Calif San Francisco, San Francisco Gen Hosp, Div Gen Internal Med, San Francisco, CA 94143 USA
[2] Wake Forest Sch Med, Div Publ Hlth Sci, Social Sci & Hlth Policy, Winston Salem, NC USA
[3] Wake Forest Comprehens Canc Ctr, Gen Surg, Winston Salem, NC USA
[4] Wake Forest Sch Med, Div Publ Hlth Sci, Biostat Sci, Winston Salem, NC USA
[5] NCI, Hlth Serv & Econ Branch, Appl Res Program, Div Canc Control & Populat Sci, Rockville, MD USA