1. Gastric and Colorectal Surgery Division, Department of General Surgery, Army Medical Center (Daping Hospital), Army Medical University, Chongqing, China
2. Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
3. Department of Colorectal and Anal Surgery, The 940th Hospital of Joint Logistics Support Force of The Chinese People's Liberation Army, Gansu, China
4. Department of Gastrointestinal and Hernia Surgery, Second People’s Hospital of Yibin, Yibin, China
5. Department of Gastrointestinal Surgery, The First Affiliated Hospital of Air Force Medical University, Xi’an, China
6. Department of Gastrointestinal Surgery, Yongchuan Hospital of Chongqing Medical University, Chongqing, China
7. Department of Gastrointestinal and Breast Surgery, The People's Hospital of Kaizhou District, Chongqing, China
8. Department of Epidemiology, College of Preventive Medicine, Army Medical University, Chongqing, China