1. Clinical Epidemiology and EBM Center, National Clinical Research Center for Digestive Diseases, Beijing Friendship Hospital, Capital Medical University, Beijing, China
2. Peking University Clinical Research Institute, Peking University Health Science Center, Beijing, China
3. The George Institute for Global Health at Peking University Health Science Center, Beijing, China
4. Department of Cardiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China