[1] Univ Minnesota, St Paul, MN 55108 USA
[2] Univ Pittsburgh, Inst Canc, Div Canc Control & Populat Sci, Pittsburgh, PA USA
[3] Univ So Calif, Keck Sch Med, Dept Prevent Med, Los Angeles, CA 90033 USA
[4] Univ Pittsburgh, Grad Sch Publ Hlth, Dept Epidemiol, Div Canc Control & Populat Sci, Pittsburgh, PA USA