CKD-EPI Creatinine Equation (2021)

Expressed as a single equation:

eGFR_cr = 142 x min(S_cr/κ, 1)^α x max(S_cr/κ, 1)^-1.200 x 0.9938^Age x 1.012 [if female]

where:

S_cr = standardized serum creatinine in mg/dL

κ = 0.7 (females) or 0.9 (males)

α = -0.241 (female) or -0.302 (male)

min(S_cr/κ, 1) is the minimum of S_cr/κ or 1.0

max(S_cr/κ, 1) is the maximum of S_cr/κ or 1.0

Age (years)

Assays

Creatinine is assayed using methods that are traceable to IDMS assigned NIST certified reference materials. To learn more, go to nkdep.nih.gov.

Recommended method for estimating GFR in adults.
Designed for use with laboratory creatinine values that are standardized to IDMS.
Estimates GFR from serum creatinine, age, sex, and race.
More accurate than the MDRD Study equation, particularly in people with higher levels of GFR.
Based on the same four variables as the MDRD Study equation, but uses a 2-slope “spline” to model the relationship between estimated GFR and serum creatinine, and a different relationship for age, sex and race.
Some clinical laboratories are still reporting GFR estimates using the MDRD Study equation. The National Kidney Foundation has recommended that clinical laboratories should begin using the CKD-EPI equation to report estimated GFR in adults.
Developed in 2009 by the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI).

Levey AS, Stevens LA, Schmid CH, et al. A new equation to estimate glomerular filtration rate. Ann Intern Med. 2009;150(9):604-612.
Levey AS, Stevens LA. Estimating GFR using the CKD Epidemiology Collaboration (CKD-EPI) creatinine equation: more accurate GFR estimates, lower CKD prevalence estimates, and better risk predictions. Am J Kidney Dis. 2010;55(4):622-627.
Matsushita K, Selvin E, Bash LD, Astor BC, Coresh J. Risk implications of the new CKD Epidemiology Collaboration (CKD-EPI) equation compared with the MDRD Study equation for estimated GFR: the Atherosclerosis Risk in Communities (ARIC) Study. Am J Kidney Dis. 2010;55(4):648-659.
White SL, Polkinghorne KR, Atkins RC, Chadban SJ. Comparison of the prevalence and mortality risk of CKD in Australia using the CKD Epidemiology Collaboration (CKD-EPI) and Modification of Diet in Renal Disease (MDRD) Study GFR estimating equations: the AusDiab (Australian Diabetes, Obesity and Lifestyle) Study. Am J Kidney Dis. 2010;55(4):660-670.
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Inker, AS. Frequently Asked Questions About GFR Estimates. New York: The National Kidney Foundation; 2011