Purpose of review: To discuss the most commonly used creatinine-based glomerular filtration rate (GFR) estimating equations, focus on the modification of diet in renal disease (MDRD) equation and the chronic kidney disease epidemiology collaboration (CKD-EPI) equation, and review studies that have directly compared their performance, estimated the prevalence of chronic kidney disease (CKD), and assessed prognosis related to each equation.
Recent findings: The CKD-EPI equation was published in 2009 and appears to be more generalizable and accurate for estimating GFR in comparison with the MDRD equation. Compared with the MDRD study equation, the CKD-EPI equation results in a lower prevalence of CKD and a more accurate assessment of prognosis, particularly when estimated GFR is greater than 60 ml/min/1.73 m(2).
Summary: The CKD-EPI equation appears to be a more generalizable and accurate equation for estimating GFR in comparison with the MDRD equation. Additional studies in subgroups such as the elderly, in the general population where individuals are not selected for being at high risk of CKD, and across different race/ethnic populations are needed in order to further generalize these findings. In the meantime, there is accumulating evidence to support the recommendation that the CKD-EPI equation should replace the MDRD equation.