Table 4.

Center Level Analysis: Association of baseline withdrawal time with adenoma detection rates at baseline, average polyp size at baseline, and risk of neoplasia at 5 years in those that returned for follow up.

Center	Baseline Colonoscopy					Interval Colonoscopy
	Number of cases	WT (min) in patients without polyps	Adenomas (%)	Advanced Neoplasia (%)	Mean Polyp Size (mm)	Number of cases	Interval Neoplasia (%)	Interval Advanced Neoplasia (%)
1	413	5.2	17.7	8.0	7.0	112	41.1	13.4
2	274	8.6	39.1	7.3	4.0	108	31.5	1.9
3	129	8.7	34.1	8.5	5.2	57	33.3	5.3
4	163	10.2	39.3	16.6	5.9	66	47.0	4.6
5	288	11.6	39.9	14.9	6.5	86	27.9	4.7
6	305	11.6	42.0	10.5	4.6	141	41.1	8.5
7	252	12.6	36.9	7.9	4.3	88	33.0	4.6
8	273	14.4	43.2	6.6	5.2	111	55.9	15.3
9	295	14.7	35.9	12.5	5.9	96	40.6	9.4
10	150	16.8	48.7	14.0	4.9	53	32.1	9.4
11	189	18.5	38.1	11.6	4.3	79	26.6	3.8
12	141	24.5	46.8	9.2	4.0	85	64.7	5.9
13	237	25.6	43.5	11.4	4.5	111	45.1	9.9
Correlation Coefficient of baseline WT with :			0.608 (p=0.03)	0.256 (p=0.40)	−0.420 (p=0.15)	n/a	0.156 (p=0.61)	0.212 (p=0.48)