1. Department of Endocrinology, Beijing Tongren Hospital, Capital Medical University, Beijing, China;
2. Beijing Institute of Geriatrics and Beijing Hospital, Ministry of Health, Beijing, China;
3. Cuigezhuang Community Health Service Center, Beijing, China;
4. Jinsong Community Health Service Center, Beijing, China;
5. Yuetan Community Health Service Center of, Fuxing Hospital, Capital Medical University, Beijing, China;
6. Xinjiekou Community Health Service Center, Beijing, China;
7. Department of Endocrinology, Beijing Aerospace General Hospital, Beijing, China;
8. School Hospital of Central University for Nationalities, Beijing, China;
9. Aerospace Central Hospital, Beijing, China.