1 School of Public Health, Central South University, Changsha, Hunan, China; Hunan Provincial Maternal and Child Care Hospital, Changsha, Hunan, China.
2 University of Washington, Beijing, China; Sun Yat-Sen University School of Public Health, Sun Yat-Sen Global Health Institute, Guangzhou 510080, China. Electronic address: [email protected].
3 Department of Psychiatry, University of Rochester Medical Center, Rochester, NY, USA.