1. Office of Cancer Screening, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing, China
2. Department of Gastroenterology, Gansu Wuwei Tumor Hospital , Wuwei, China
3. Department of Epidemiology, Cancer Institute/Hospital of Ci County , Handan, China
4. Department of General Surgery, Linzhou Cancer Hospital , Linzhou, China
5. Office of National Cancer Regional Medical Centre in Liaoning Province, The First Affiliated Hospital of China Medical University , Shenyang, China
6. Department of Public Health, Erasmus MC, University Medical Center Rotterdam , Rotterdam, the Netherlands