Affiliation: | 1. Tianjin Women's and Children's Health Center, , Tianjin, China;2. Pennington Biomedical Research Center, , Baton Rouge, Louisiana, USA;3. Population Cancer Research program, Dalhousie University, , Halifax, NS, Canada;4. Department of Epidemiology and Biostatistics, Tianjin Medical University, , Tianjin, China |