1. The First Clinical Medicine College, Gansu University of Chinese Medicine, Lanzhou, Gansu, China
2. Department of General Surgery, Gansu Provincial People’s Hospital, Lanzhou, Gansu, China
3. General Hospital of Ningxia Medical University, Yinchuan, Ningxia, China
4. Evidence-Based Medicine Center, School of Basic Medical Sciences, Lanzhou University, Lanzhou, Gansu, China
5. Institution of Clinical Research and Evidence Based Medicine, Gansu Provincial People’s Hospital, Lanzhou, Gansu, China
6. Key Laboratory of Evidence Based Medicine and Knowledge Translation of Gansu Province, Lanzhou University, Lanzhou, Gansu, China