1. School of Public Policy and Administration, Northwestern Polytechnical University, Xi’an, China
2. School of Marxism, Xi’an Jiaotong University, Xi’an, China
3. Institute for Research on Health Information and Technology, School of Public Health, Xi’an Medical University, Xi’an, China
4. International Centre for Reproductive Health, Department of Public Health and Primary Care, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium
5. School of Public Health, Hebei Medical University, Shijiazhuang, China
6. Social Medicine Center, National Research Institute for Family Planning, Beijing, China
7. School of Public Health, Université Libre de Bruxelles (ULB), Brussels, Belgium