Table 3.

K/DOQI-CKD classification of the population by CG and MDRD formulas^a

mGFR^b	n	Stage 1		Stage 2		Stage 3		Stage 4		Stage 5
		eGFR ≥90		eGFR 60 to 89.9		eGFR 30 to 59.9		eGFR 15 to 29.9		eGFR <15
		CG	MDRD	CG	MDRD	CG	MDRD	CG	MDRD	CG	MDRD
≥90	807	64.4	49.1	33.8	47.8	1.7	3.1	0	0	0	0
60 to 89.9	512	20.9	12.9	52.9	55.9	26.0	31.1	0.2	0.2	0	0
30 to 59.9	484	1.9	0.6	17.6	10.5	70.9	72.9	9.7	15.9	0	0
15 to 29.9	275	0	0	2.5	0.0	25.5	19.6	61.8	53.5	10.2	26.9
<15	130	0	0	0	0	5.4	0	50.8	40.0	43.8	60.0

↵^a Data presented in %. K/DOQI, Kidney Disease Outcomes Quality Initiative; CKD, chronic kidney disease; CG, Cockcroft-Gault formula; MDRD, Modification of Diet in Renal Disease formula; mGFR, measured glomerular filtration rate by renal inulin clearance (ml/min/1.73 m²); eGFR, estimated GFR (ml/min/1.73 m²) by CG or MDRD formula used for CKD classification (stages based on GFR levels alone). Values in bold represent percentage of properly classified estimates by either formula.