1. Department of Anesthesiology, Affiliated Hospital of Chengdu University, Chengdu, Sichuan
2. Department of Anesthesiology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou
3. Suzhou Medical College of Soochow University, Suzhou, Jiangsu
4. School of Health, Brooks College, Sunnyvale, CA
5. Department of General Practice, Anhui Medical University, He Fei, Anhui, China