1. Department of Epidemiology and Biostatistics, School of Public Health; Tianjin Medical University; Tianjin China
2. Department of Health Statistics, School of Public Health and Management; Weifang Medical University; Shandong China
3. Department of Endocrinology; Peking University People's Hospital; Beijing China
4. Department of Endocrinology; Chinese PLA General Hospital; Beijing China
5. Department of Endocrinology; Peking University First Hospital; Beijing China