1. Department of Occupational and Environmental Hygiene, School of Public Health and Management, Research Center for Medicine and Social Development, Innovation Center for Social Risk Governance in Health, Chongqing Medical University, Chongqing, China
2. Chengdu Center for Disease Control & Prevention, Chengdu, China
3. China-Canada-New Zealand Joint Laboratory of Maternal and Fetal Medicine, Chongqing Medical University, Chongqing, China
4. The Liggins Institute, University of Auckland, Auckland, New Zealand
5. Department of Statistics, School of Public Health and Management, Chongqing Medical University, Chongqing, China
6. College of Medicine, Biological Sciences and Psychology, University of Leicester, Leicester LE1 9HN, UK