[1] NCI, Div Canc Epidemiol & Genet, NIH, Bethesda, MD 20892 USA
[2] Univ London London Sch Hyg & Trop Med, London WC1E 7HT, England
[3] Ctr Dis Control & Prevent, Div Canc Prevent & Control, Atlanta, GA USA
[4] Rollins Sch Publ Hlth, Dept Biostat, Atlanta, GA USA
[5] Fred Hutchinson Canc Res Grp, Seattle, WA USA
[6] Columbia Univ, Sch Publ Hlth, Div Epidemiol, New York, NY 10027 USA