Published on in Vol 6 , No 1 (2018) :January

1 The George Institute for Global Health, Peking University Health Science Center, Beijing, CN
2 School of Public Health, Peking University Health Science Center, Beijing, CN
3 School of Public Health, Hebei Medical University, Shijiazhuang, CN
4 Faculty of Medicine, University of New South Wales, Sydney, AU
*these authors contributed equally