[1] PATH, Seattle, WA USA
[2] Chinese Acad Med Sci, Canc Inst & Hosp, Beijing 100730, Peoples R China
[3] Peking Union Med Coll, Beijing 100021, Peoples R China
[4] Univ Virginia, Dept Pathol, Charlottesville, VA 22903 USA
[5] Global Coalit Cerv Canc, Chestertown, MD USA
[6] Albert Einstein Coll Med, Dept Epidemiol & Populat Hlth, Bronx, NY 10467 USA