1. Department of Epidemiology and Biostatistics, School of Public Health, Jilin University, Xinmin Street No.1163, Changchun, 130021, P. R. China
2. The First Affiliated Hospital of Xi'an Jiaotong University, No. 69, Xiaozhai West Road, Xi'an, 710061, P. R. China
3. Global Health Institute, School of Public Health, Xi'an Jiaotong University, Xi'an, Shaanxi, 710100, P. R. China