Clinical Research Directory

Inclusion Criteria: 1. Age 18-75 years old 2. Patients or family members were able to understand the study protocol and willing to participate in this study by signing informed consent. 3. Those who underwent colonoscopy at the Gastrointestinal Endoscopy Center of Peking Union Medical College Hospital. Exclusion Criteria: 1. Patients who have taken colonoscopy before 2. Patients who are unable to read or write 3. Patients with severe mental disorders, organic brain mental disorders 4. those with poor bowel preparation (BBPS \< 6 ) 5. patients with chronic constipation, history of intestinal diverticula 6. Patients who have undergone previous colorectal surgery 7. those with previous findings of severe colonic strictures or obstructive tumors 8. patients who are pregnant or breastfeeding 9. patients with severe infectious diseases. 10. Patients with inflammatory bowel disease, familial polyposis.