[1] Temple Univ, Epidemiol & Biostat, Philadelphia, PA 19122 USA
[2] Fox Chase Canc Ctr, Canc Prevent & Control, 7701 Burholme Ave, Philadelphia, PA 19111 USA
[3] Univ Hong Kong, Dept Clin Oncol, Hong Kong, Peoples R China
[4] Univ Hong Kong, Dept English, Hong Kong, Peoples R China