[1] Canc Prevent Inst Calif, Fremont, CA 94538 USA
[2] Stanford Canc Inst, Stanford, CA USA
[3] Stanford Univ, Sch Med, Dept Hlth Res & Policy, Div Epidemiol, Stanford, CA 94305 USA
[4] NCI, Surveillance Res Program, Div Canc Control & Populat Sci, Bethesda, MD 20892 USA
[5] Univ Calif Merced, Sch Social Sci Humanities & Arts, Social Cognit Sci Grad Grp, Merced, CA USA
[6] Stanford Univ, Dept Med, Sch Med, Div Oncol, Stanford, CA 94305 USA