Clinical Research Directory

Inclusion Criteria: * Male or female aged 18 years or older who undergo colonoscopy. Exclusion Criteria: * 1)No pathological result. * 2\) No or invalid contact information. * 3\) The surveillance interval cannot be determined according to the surveillance guidelines, including poor bowel preparation, colorectal cancer or suspicious malignance, surgery or colorectal ESD history, those who fail to complete colonoscopy due to unbearable, pathological indications of not polyps, hamartoma or lymphoma polyps, history of ulcerative colitis, and so on. * 4\) Has participated in other clinical trials, signed the informed consent form and is in the surveillance period of other clinical trials. * 5\) Have drug or alcohol abuse or psychological disorder in the past five years. * 6）Pregnancy. * 7）Not suitable for recruitment after investigator evaluation because of other high-risk conditions.