1. West China Hospital, Sichuan University; Department of Geriatrics; No. 37 Guo Xue Xiang Street Chengdu Sichuan China 610041
2. No.5 People's Hospital of Chengdu; Intensive Care Department; Chengdu Sichuan China 610041
3. Xi'an No.4 Hospital, Xi'an JiaoTong University; Department of Ophthalmology; No.21, Jie Fang Road Xi'an Shaanxi China 710004
4. West China Hospital, Sichuan University; Chinese Cochrane Centre, Chinese Evidence-Based Medicine Centre; No. 37, Guo Xue Xiang Chengdu Sichuan China 610041