9 Minutes for Colonoscopy Withdrawal

Study Overview
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Brief Summary
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A withdrawal time of at least 6 minutes has been considered to be necessary to guarantee the adenoma detection rate and the critical quality criterion of colonoscopy. However, several large observational investigations demonstrated that 9 minutes will be in favor of higher adenoma detection rate and lower risk of interval colorectal cancer, when compared with 6-minute withdrawal. Meanwhile, a few studies also indicated that no significant benefit were observed in longer withdrawal time. Up to now, no randomized controlled trials have been conducted to give a definitive conclusion. Therefore, we performed a multicenter, prospective, randomized Controlled trial to compare adenoma detection rate of 6-minute and 9-minute withdrawal in colonoscopy.

Official Title
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Impact of 9-minute Withdrawal Time on Adenoma Detection Rate：a Multicenter, Prospective, Randomized Controlled Trial

Conditions
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Colon Polyps, Colorectal Adenomas

Intervention / Treatment
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* Procedure: 9-minute withdrawal
* Procedure: 6-minute withdrawal


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients whose age is between 40-85. Patients who have indications for screening, surveillance and diagnostic colonoscopy. Patients who have signed inform consent form Exclusion Criteria: Patients who have undergone colonic resection Patients with intracranial and/or central nervous system disease, including cerebral infarction and cerebral hemorrhage. Patients with severe chronic cardiopulmonary and renal disease. Patients who are unwilling or unable to consent. Patients who are not suitable for colonoscopy Patients who received urgent or therapeutic colonoscopy Patients with pregnancy, inflammatory bowel disease, polyposis of colon, colorectal cancer, or intestinal obstruction Patients who are taking aspirin, clopidogrel or other anticoagulants Patients with Aronchick score > 3

Ages Eligible for Study
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Minimum Age: 40 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 9-minute withdrawal group<br>Patients in 9-minute withdrawal group will be carefully observed for 9 minutes during the colonoscopy withdraw. A stop watch will be utilized to remind endoscopists the withdrawal time. The time to perform polyp biopsy will not be included in the 9 minutes. | Procedure: 9-minute withdrawal<br>* Patients in 9-minute withdrawal group will be carefully observed for 9 minutes during the colonoscopy withdraw<br>|
| Active Comparator: 6-minute withdrawal group<br>Patients in 6-minute withdrawal group will be carefully observed for 6 minutes during the colonoscopy withdraw. A stop watch will be utilized to remind endoscopists the withdrawal time. The time to perform polyp biopsy willwill not be included in the 9 minutes. | Procedure: 6-minute withdrawal<br>* Patients in 6-minute withdrawal group will be carefully observed for 6 minutes during the colonoscopy withdraw<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| adenoma detection rate(ADR) | ADR was calculated adenoma detection rate is the number of patients with at least one adenoma, divided by the total number of patients. | 30mins | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| adenomas per colonoscopy(APC) | APC was calculated as the number of adenomas detected during colonoscopy withdraw divided by the number of colonoscopies. | 30mins |