Estimated Glomerular Filtration Rate Correlates Poorly with Four-Hour Creatinine Clearance in Critically Ill Patients with Acute Kidney Injury

Table 3

A summary of the performance of eGFR equations in critically ill patients with AKI, whose ⁴CrCl was less than 60 mL·min⁻¹  per 1.73 m² and whose urine output was greater than 0.2 mL·kg⁻¹ per min during the study period (37 patients).

	^4CrCl	1/creatinine	Cockcroft and Gault	aMDRD	MDRD 6	MDRD 7	CKD EPI	Cystatin; C 1	Cystatin; C 3	Cystatin; C 4
Mean eGFR; (mL·min^−1 per 1.73 m^2)	27.1*	53.4	35.5	33.3	35.5	28.8	32.3	43.2	41.0	39.7
Range; (mL·min^−1 per 1.73 m^2)	8–51	13–119	11–63	9–87	9–79	8–71	9–80	17–85	16–79	15–79
r ^2 correlation (P < 0.0001)		0.64	0.82	0.72	0.75	0.71	0.70	0.71	0.71	0.70
Bias		−26.3	−8.4	−6.2	−5.4	−1.6	−5.2	−16.1	−13.9	−12.5
(1.96×SD)		28	13.72	18.6	16.66	16.6	18.33	20.14	19.36	16.6
Percentage error (precision)		52	39	56	47	58	57	46	47	42
Accuracy (%)
10%		3	16	16	27	16	24	11	14	16
30% (P30)		5	46	57	49	70	57	27	30	35
50%		22	68	78	76	86	81	46	54	59

∗Measured not estimated.