Effect of Colonoscopy Volume on Quality Indicators

Table 1

Distribution of potential confounding variables within the five endoscopist annual colonoscopy volume quintiles.

	Quintile 1	Quintile 2	Quintile 3	Quintile 4	Quintile 5	value
	0–149	150–249	250–301	302–530	>530
Mean age (years)	57.8	59.5	58.9	58.9	57.4	0.014
Gender (% male)	46.0	50.4	41.5	39.7	46.3	0.002
ASA score (% 1 or 2)	86.1	94.9	87.3	81.0	85.3	<0.001
Indication (% screening or surveillance)	57.2	68.4	51.8	58.4	66.1	<0.001
Ratio of general surgeons to gastroenterologists (% surgeon)	5 : 0	4 : 0	2 : 2	2 : 2	0 : 4	<0.001
	100	100	50	50	0