Institutional belief · Medicine and clinical algorithms
Race-based kidney-function correction
Black race was treated as a physiological variable that justified automatically increasing estimated kidney function for Black patients with otherwise identical creatinine-based inputs.
1 episode
Current understanding
Current understanding
Race is a social rather than biological category and is too imprecise to serve as a blanket physiological correction in kidney-function equations. Current U.S. guidance recommends race-free eGFR equations, with cystatin C or measured GFR used when greater precision is needed.
Institutional episode
United States
The MDRD equation published in 1999 included a higher eGFR coefficient for patients classified as Black. In 2002, National Kidney Foundation KDOQI guidelines recommended the MDRD equation for adults and advised clinical laboratories to report equation-based GFR estimates; the 2009 CKD-EPI equation retained a Black race coefficient and became widely used. In 2021, the National Kidney Foundation and American Society of Nephrology recommended immediate adoption of a new race-free equation, concluding that a uniform approach without a race variable was preferable for U.S. clinical care.
Institutions
- National Kidney Foundation — Kidney Disease Outcomes Quality Initiative (KDOQI)
- Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI)
Documented consequences
- Race-dependent chronic-kidney-disease staging
- Potential delay of nephrology and transplant referral
- Race-dependent medication and treatment thresholds
Institutional machinery
The 1999 MDRD equation introduced a Black race coefficient in the research literature. Institutional adoption is dated here from 2002, when the National Kidney Foundation’s KDOQI guideline recommended the MDRD equation and instructed clinical laboratories to report estimated GFR. CKD-EPI later published another widely adopted race-inclusive equation in 2009. Laboratories and electronic health-record systems implemented these equations across many organizations; that distributed implementation is described as machinery rather than listed as a single institution. In 2021, the joint NKF–ASN task force recommended immediate adoption of a race-free equation.
Sources and what they establish
- KDOQI Clinical Practice Guidelines — Guideline 4, Estimation of GFRNational Kidney Foundation
- A Unifying Approach for GFR Estimation — Recommendations of the NKF-ASN Task ForceJournal of the American Society of Nephrology
- National Kidney Foundation Laboratory Engagement Working Group Recommendations for Implementing the CKD-EPI 2021 Race-Free EquationsClinical Chemistry
Documents widespread U.S. laboratory use of MDRD and CKD-EPI equations containing a Black race coefficient and the rationale and implementation steps for replacing them with race-free equations.
Last reviewed: 23/08/2026