Table 2.

Comorbidities by Procedure Category in Study Population Compared to Nonstudy Hospital Population

	Procedure Category
	Hip		Knee		Colectomy for Cancer		Colectomy not for CA		Thoracotomy
	In Study	Not In Study	In Study	Not In Study	In Study	Not In Study	In Study	Not In Study	In Study	Not In Study
Comorbidities	N = 3,920	N = 34,163	N = 5,885	N = 84,141	N = 2,391	N = 16,440	N = 1,168	N = 8,171	N = 2,550	N = 11,480
Mean Number of Comorbidities	2.45	2.46	2.36c	2.43	3.91d	4.06	3.22	3.34	4.72	4.73
Hx CHF (%)	9.26a	8.32	7.39c	8.52	17.61b	19.93	16.87c	20.51	14.39e	17.46
Hx AMI (%)	5.97	5.63	4.38	4.50	7.40	6.85	5.74	6.02	8.51	8.88
Hx Diabetes (%)	19.36	19.15	24.91	25.48	27.65b	30.38	25.51	26.44	23.10	23.48
Hx Cancer (%)	18.72	18.29	14.43	14.47	N/A	N/A	27.91	25.82	90.35f	87.54

In Study N = 15,914; Not In Study N = 154,395 in Texas, Illinois or New York with study eligible procedures and not in the 47 study hospitals

^aP-values compare in study to not in study < 0.05;

^b< 0.01;

^c< 0.005;

^d< 0.001;

^e< 0.0005;

^f<0.0001