1. Department of Gastroenterology, Beijing Friendship Hospital, Capital Medical University, National Clinical Research Center for Digestive Disease, Beijing Digestive Disease Center, Beijing Key Laboratory for Precancerous Lesion of Digestive Disease, Beijing 100050, China
2. Center for Applied Statistics and School of Statistics, Renmin University of China, Beijing 100872, China
3. Statistical Consulting Center, Renmin University of China, Beijing 100872, China
4. National Cancer Center, National Clinical Research Center for Cancer, Cancer Institute, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
5. Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
6. Department of Gastroenterology, Jizhong Energy Fengfeng Group Hospital, Handan, Hebei 056000, China
7. RSS and China-Re Life Joint Lab on Public Health and Risk Management, Renmin University of China, Beijing 100872, China.