(3)Random method: Enrolled patients were randomly assigned to one of the two polypectomy protocols (CSP vs. HSP) using a computer-generated random sequence. If a patient had one or more polyps, all eligible polyp swere removed using the initially assigned polypectomy protocol. (4)data collection:Laboratory data and previous colonoscopy data.Preoperative baseline data included:Patient entry sequence number,Operation method（CSP or HSP）,age,gender, take anticoagulant drugs or not(Warfarin , aspirin, clopidogrel), cause of desease, operation indications(Screening, inspection, polypectomy, fecal occult blood test positive, perianal rectal bleeding, other); Correlation check: 1.Blood routine, urine routine, stool routine + Occult Blood; 2,Liver and kidney function, electrolyte, blood sugar, blood coagulation, blood type, Rh factor, infection disease screening (hepatitis B, hepatitis C, HIV, syphilis and other); 3.Digestive tract tumor marker screening (CA19-9, CA24-2, CEA, etc.); 4.Abdominal ultrasound, electrocardiogram, chest X-ray. The postoperative data were: Bowel preparation (using the Boston Bowel Preparation Scale),Whether to insert the coloscope to the cecum, time of insertion,Whether to send the coloscope to the terminal ileum,Time from the insertion of the coloscope to thececum to Exit the colonoscope. Total time from the insertion of the colon to the exit of the colonoscopy.The number of polyps (per patient), polyp size (mm), anatomical (cecum, ascending colon, transverse colon, hepatic flexure, splenic flexure, descending colon, sigmoid colon, rectum), shape (flat, sessile,pedunculated ) , the number of polyps resected, Whether the naked eye view (NBI) is completely removed, the total operation time,whether the polyps were retrieved, postoperative hemorrhage (postoperative bleeding, hematochezia, delayed bleeding), Whether or not perforate, whether the use of hemostatic clip ( number), pathological diagnosis (tubulovillous adenoma, sessile serrated adenoma, hyperplastic polyp and other non neoplastic polyps), whether the additional EMR success after polypectomy, EMR operation time, the pathological results of EMR tissues (normal intestinal mucosa,tubulovillous adenoma, sessile serrated adenoma, Hyperplastic polyps, other non neoplastic polyps), whether the histological complete resection.