1. Department of Dermatology, West China Hospital, Sichuan University, Chengdu 610041, China
2. Medical Insurance Office, West China Hospital, Sichuan University, Chengdu 610041, China
3. Chinese Cochrane Center, West China Hospital, Sichuan University, Chengdu 610041, China
4. Center of Gerontology and Geriatrics, West China Hospital, Sichuan University, Chengdu 610041, China
5. National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu 610041, China