Department of Gastroenterology;
Beijing Shijitan Hospital;
Capital Medical University;
Beijing 100038;
China;
National Clinical Research Center for Digestive Diseases;
Beijing 100050;
China;
Department of Gastroenterology;
Peking University Ninth School of Clinical Medicine;
Beijing 100038;
China;
Department of Gastroenterology;
Beijing Friendship Hospital;
Capital Medical University;
National Clinical Research Center for Digestive Diseases;
Beijing 100050;
China;
Colorectal adenoma; Retroflexion; Right colon; Adenoma detection rate; Cancer;