[Xiaoyan Wang; Li Tian; Shuyu Ye; Xuejie Chen; Xin Xiang; Yangjie Liao; Wang, Xiaoyan] Cent South Univ, Xiangya Hosp 3, Dept Gastroenterol, Changsha 410013, Peoples R China.
[Wenya Liu; Yang, F; Fengmei Song; Yue Yang; Fei Yang] Univ South China, Sch Publ Hlth, Hengyang Med Sch, Hunan Key Lab Typ Environm Pollut & Hlth Hazards, Hengyang 421001, Peoples R China.
[Wenya Liu; Yang, F; Fei Yang] Cent South Univ, XiangYa Sch Publ Hlth, Hunan Prov Key Lab Clin Epidemiol, Changsha 410078, Peoples R China.
[Xiang Gao; Kang Chao] Sun Yat Sen Univ, Affiliated Hosp 6, Dept Gastroenterol, Guangzhou, Peoples R China.
[Qian Cao; Rongbei Liu] Zhejiang Univ, Sir Run Run Shaw Hosp, Dept Gastroenterol, Coll Med, Hangzhou 310018, Peoples R China.