Effect of Institution-Wide Policy of Colonoscopy Withdrawal Time ≥7minutes On Polyp Detection

Abstract

Aim: The aim of our study was to determine if the implementation of an institution-wide policy of colonoscopy withdrawal time ≥7 minutes was associated with an increase in colon polyp detection. Methods: The Gastroenterology division at our medical center started a quality improvement initiative of requiring all endoscopists to attain a colonoscopy withdrawal time of at least 7-minutes. Compliance with 7-minute withdrawal time was recorded for all non-therapeutic colonoscopies. Polyp detection ratio [number of polyps detected divided by number of colonoscopies performed] was computed for each day and for each month. Spearman's correlation was used to determine if there was an association between compliance with 7-minute withdrawal time and polyp detection ratio. Results: During study period [2/2006 to 6/2007] 23,910 colonoscopies were performed. The average age of patients undergoing colonoscopy was 56.8 years [range 19years-101years], and 54 % were female. Colon cancer screening or surveillance was the indication for 42.5% of colonoscopies. Compliance with 7-minute withdrawal time increased from 65% at the beginning of the initiative to almost 100%. However, no increase in polyp detection ratio was noted over the same period for all polyps [p = 0.9] or for polyps 1-5 mm [p = 0.9], 6-9 mm [p = 0.9] or ≥10 mm [p = 0.5]. No statistically significant association [Spearman's correlation] was noted between compliance with 7-minute withdrawal time and polyp detection ratio for all polyps [p = 0.2] or polyps 1-5 mm [p = 0.9], 6-9 mm [p = 0.2] or ≥10 mm [p = 0.06]. Also, no association was detected when only colonoscopies performed for screening or surveillance were analyzed [p = 0.5] or when only colonoscopies performed by experience endoscopists were analyzed [p = 0.6]. Conclusion: An institution-wide policy of colonoscopy withdrawal time ≥7 minutes did not results in an increase in the detection of colon polyps.