1. Department of Gastroenterology, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China
2. Medical Research Center, Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China
3. Clinical Epidemiology Unit International Clinical Epidemiology Network Beijing China
4. Surgical and Translational Research Centre, Faculty of Medical and Health Sciences University of Auckland Auckland New Zealand