This multicenter randomized controlled trial evaluates whether a pre-procedural risk score-based endoscopist assignment strategy reduces intraprocedural pain in high-risk patients undergoing unsedated colonoscopy. High-risk patients (risk score \>5) are randomized 1:1 to either the intervention group (examination performed by expert endoscopists with ≥5,000 colonoscopy experiences) or the control group (examination performed by endoscopists assigned per routine hospital scheduling). The primary outcome is the proportion of patients reporting moderate-to-severe pain during colonoscopy, assessed by a blinded research assistant using a 4-point VRS. A total of 106 high-risk patients will be enrolled from two centers in China.
Age 18-75 years.
Outpatient or inpatient undergoing colonoscopy for medical screening, polyp surveillance, or polypectomy.
Pre-procedural risk score >5 (based on the following scoring system: BMI <19 [5 points], female sex [1 point], history of abdominal or pelvic surgery [2 points], constipation [3 points]).
Patients who have received sedation or analgesia prior to colonoscopy.
Patients unwilling to cooperate or unable to provide informed consent.
Incomplete intestinal obstruction.
Inflammatory bowel disease, multiple polyposis syndromes, or severe chronic cardiac or pulmonary disease.