Table 6.

Prevalence of CKD Stages 1–4: Sex-Specific Albumin-Creatinine Ratio Cut Points: MDRD Study vs. Mayo vs. Cockcroft-Gault Estimating Equations

	Estimating Equation
	MDRD Study			Mayo				Cockcroft-Gault
CKD Stage	Prevalence %*	95% CI	Population n†	Prevalence %*	95% CI	Population n†	Prevalence Ratio‡	Prevalence %*	95% CI	Population n†	Prevalence Ratio§
1	3.09	2.82–3.37	6,705,123	3.82	3.48–4.18	8,301,600	1.23	2.77	2.52–3.04	6,019,747	0.90
2	4.55	4.18–4.94	9,883,203	3.81	3.41–4.24	8,279,868	0.84	3.62	3.29–3.99	7,866,961	0.79
3	7.98	7.31–8.71	17,344,870	5.78	5.31–6.29	12,561,060	0.72	17.31	16.45–18.21	37,617,984	2.17
4	0.35	0.27–0.47	768,757	0.52	0.41–0.67	1,130,061	1.47	1.15	0.97–1.38	2,499,173	3.23
1–4	15.97	15.16–16.81	34,701,953	13.93	13.23–14.65	30,272,589	0.87	24.86	23.82–25.93	54,025,597	1.56
3–4	8.34	7.66–9.07	18,113,627	6.30	5.80–6.85	13,691,121	0.76	18.47	17.52–19.45	40,138,889	2.22

Abbreviations: CI, confidence interval; CKD, chronic kidney disease; MDRD, Modification of Diet in Renal Disease.

^*Prevalence estimates of stages 1 and 2 incorporate persistence estimates for microalbuminuria of 53.9% if estimated glomerular filtration rate ≥ 90 mL/min/1.73 m² (≥ 1.50 mL/s/1.73 m²) and 72.7% if 60–89 mL/min/1.73 m² (1.00–1.48 mL/s/1.73 m²).

^†Population n based on the estimated 2006 US population aged 20 years and older: 217,319,378.

^‡Mayo:MDRD

^§Cockcroft-Gault:MDRD