Table 3. Covariates associated with severe anemia.

	Estimate	SE	p	OR	95% CI for OR
Center			0,005
A	Reference
B	-0.834	0.262	0.001	0.434	0.260–0.725
C	0.020	0.312	0.950	1.020	0.553–1.880
Gender, Male	Reference
Female	0.493	0.223	0.027	1.637	1.058–2.533
Ferritin < 100	Reference
Ferritin ≥ 100	0,763	0.229	0.001	2.144	1.368–3.362
CRP	0,008	0,004	0,064	1,008	1,000–1,016
Iron	-0.009	0.004	0.041	0.991	0.983–0.999
e-GFR	-0,050	0.009	0.000	0.951	0.935–0.967
Constant	0.142	0.365	0.697	1.153

CI: confidence interval, eGFR: estimated glomerular filtration rate, OR: odds ratio, SE: standard error