Confounders of mortality and hospitalization rate calculations for profit and nonprofit dialysis facilities: analytic augmentation

Table 2 Comparison of additional potential confounding factors between for-profit and not-for-profit facilities

	For-Profit N = 366,011		Not-For-Profit N = 34,029		P-value
	N	Percent	N	Percent	P-value
Facility length of ownership					< 0.001
2 years	9,106	2.5	888	2.6
3 years	12,350	3.4	917	2.7
≥ 4 years	344,555	94.1	32,224	94.7
Vascular access at first treatment					< 0.001
Catheter	208,016	78.0	18,182	75.6
Fistula	45,243	17.0	4,731	19.7
Graft	10,999	4.1	950	4.0
Other	2,605	1.0	174	0.7
Length of predialysis care					< 0.001
> 12 months	76,905	30.4	8,915	37.2
6-12 months	62,785	24.8	5,868	24.4
< 6 months	36,510	14.4	3,165	13.2
None	76,662	30.3	6,050	25.2
ESRD network region					< 0.001
1	11,036	3.0	629	1.9
2	15,084	4.1	3,339	9.8
3	8,373	2.3	662	2.0
4	16,002	4.4	1,565	4.6
5	21,864	6.0	791	2.3
6	37,720	10.3	4,804	14.1
7	26,229	7.2	1,110	3.3
8	22,549	6.2	3,220	9.5
9	28,838	7.9	2,259	6.6
10	16,832	4.6	76	0.2
11	18,171	5.0	3,223	9.5
12	12,401	3.4	2,290	6.7
13	17,128	4.7	614	1.8
14	39,625	10.8	284	0.8
15	17,924	4.9	2,201	6.5
16	8,122	2.2	2,963	8.7
17	16,108	4.4	3,330	9.8
18	32,005	8.7	669	2.0

ISSN: 1471-2369