1. Department of Gastroenterology, Shanghai Pudong Hospital, Fudan University Pudong Medical Center, Shanghai, China
2. Department of Gastroenterology, the Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou, China
3. Department of Gastroenterology, The Second Affiliated Hospital of Xi’an Jiaotong University, Xi’an, China
4. Department of Citizen Health, Community Health Service Center of Jinxi Town, Kunshan, China