# MDRD for Adults (SI Units)

Recommended eGFR equations will be changing. Once guidance is adopted, we will update this content accordingly.

In adults, the most widely-used equations for estimating glomerular filtration rate (GFR) from serum creatinine are the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation1 and the isotope dilution mass spectrometry (IDMS) traceable Modification of Diet in Renal Disease (MDRD) Study equation2. The NIDDK’s calculators rely on creatinine determinations which are isotope dilution mass spectrometry (IDMS) traceable. All laboratories should be using creatinine methods calibrated to be IDMS traceable. Read more about creatinine standardization.

This IDMS-traceable MDRD study equation calculator should be used when Scr is reported in µmol/L. This equation should not be used when eGFR values above 60 mL/min/1.73 m² are desired.

GFR (mL/min/1.73 m²) = 175 × (Scr/88.4)-1.154 × (Age)-0.203 × (0.742 if female) × (1.212 if African American) (SI units)

The equation does not require weight because the results are reported normalized to 1.73 m² body surface area, which is an accepted average adult surface area.

Enter a numeric value of at least 0.001
Enter a numeric age, 18 or over
African American?
Gender
GFR value (mL/min/1.73 m²**)
mL/min/1.73 m²

*This equation should only be used for patients 18 and older.

**The NIDDK presently recommends using the CKD-EPI calculator for reporting estimated GFR values greater than or equal to 60 mL/min/1.73 m².

All estimating equations used in adult populations become less accurate as GFR increases, such as in people with normal kidney function. 3, 4

## References

1. Levey AS, Stevens LA, Schmid CH, Zhang YL, Castro AF, 3rd, Feldman HI, et al. A new equation to estimate glomerular filtration rate. Ann Intern Med. 2009;150(9):604-12.

2. Levey AS, Coresh J, Greene T, Stevens LA, Zhang YL, Hendriksen S, Kusek JW, Van Lente F; Chronic Kidney Disease Epidemiology Collaboration. Using standardized serum creatinine values in the modification of diet in renal disease study equation for estimating glomerular filtration rate. Ann Intern Med. 2006 Aug 15;145(4):247-54.

3. Poggio ED, Wang X, Greene T, Van Lente F, Hall PM. Performance of the modification of diet in renal disease and Cockcroft-Gault equations in the estimation of GFR in health and in chronic kidney disease. Journal of the American Society of Nephrology. 2005;16(2):459–466.

4. Levey AS, Bosch JP, Lewis JB, Greene T, Rogers N, Roth D.; A more accurate method to estimate glomerular filtration rate from serum creatinine: a new prediction equation. Modification of Diet in Renal Disease Study Group. Ann Intern Med. 1999 Mar 16;130(6):461-70.