1. National Center for Women and Children’s Health, Chinese Center for Disease Control and Prevention, Beijing, China.
2. National Center for Chronic and Noncommunicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
3. National Health and Family Planning Commission of the People’s Republic of China, No.1, Xizhimen South Road, Xicheng District, Beijing, China.
4. Vanderbilt Institute for Global Health and Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, United States of America.