[1] Second Mil Med Univ, Dept Gastroenterol, Changhai Hosp, Shanghai 200433, Peoples R China
[2] Second Mil Med Univ, Ctr Clin Epidemiol & Evidence Based Med, Shanghai 200433, Peoples R China
[3] Second Mil Med Univ, Dept Endocrinol, Changhai Hosp, Shanghai 200433, Peoples R China
[4] Fudan Univ, Zhongshan Hosp, Dept Gen Surg, Shanghai 200433, Peoples R China
[5] Shanghai Jiao Tong Univ, Ruijin Hosp, Sch Med, Dept Gastroenterol, Shanghai 200030, Peoples R China