Zhao Li 1,West China School of Public Health, Sichuan University and West China Fourth Hospital; Fan Yanjun 2,Maternal and Child Health Center, Chinese Center for Disease Control and Prevention; Wang Yuanyuan is Research Assistant, Peking University Third Hospital;Zhang Yanan3, Maternal and Child Health Center, Chinese Center for Disease Control and Prevention.
Online:2019-05-29
Published:2019-07-05
About author:Zhao Li is Associate Professor, West China School of Public Health, Sichuan University and West China Fourth Hospital; Fan Yanjun is Researcher of Maternal and Child Health Center, Chinese Center for Disease Control and Prevention; Wang Yuanyuan is Research Assistant, Peking University Third Hospital;Zhang Yanan is Postgraduate Student, Maternal and Child Health Center, Chinese Center for Disease Control and Prevention.