Table 3.

National estimates of emergency department (ED) volume and surgery rate for diverticulitis, 2006–2011.

Year	National estimate of ED visits	In dataset (N)	Admitted (n)	Percentage rate of surgery for all patients (95% CI)	Percentage rate of surgery for admitted (95% CI)*	Percentage rate of surgery for all low-risk patients (95% CI)**	Percentage rate of surgery for admitted, low-risk patients (95%CI)***
2006	238,248	50,636	28,392	6.46 (6.15, 6.77)	11.72 (11.17, 12.27)	4.01 (3.59,4.41)	11.53 (10.40, 12.67)
2007	253,092	54,531	29,444	5.71 (5.42, 5.99)	10.73(10.18, 11.29)	3.59 (3.20,3.98)	11.31 (10.17, 12.47)
2008	257,257	59,191	30,968	5.51 (5.22,5.79)	10.792(10.25, 11.33)	3.00 (2.65, 3.36)	10.20 (9.00, 11.40)
2009	268,111	60,437	31,164	5.03 (4.78, 5.27)	9.98 (9.49, 10.47)	2.66 (2.33, 3.00)	9.12 (8.04, 10.21)
2010	280,398	62,231	31,660	4.99 (4.74, 5.24)	10.10 (9.56, 10.64)	2.40 (2.10, 2.70)	8.89 (7.76, 10.03)
2011	302,612	67,959	32,848	4.74 (4.51, 4.97)	10.00 (9.51, 10.49)	2.20 (1.91, 2.48)	8.51 (7.44, 9.57)
Average	266,620	59,164	30,744	5.36 (5.25, 5.47)	10.54(5.25, 5.47)	2.96 (2.82, 3.10)	10.01 (9.55, 10.48)

^*p<0.001 trend,

^**p<0.001 trend,

^***p<0.01 trend.