Correcting a race-based kidney formula added 1.7 years of wait time priority for Black transplant candidates

JAMA Internal Medicine, March 2026

For decades, a widely used equation for estimating kidney function assigned higher values to Black patients simply because of their race. The formula made their kidneys appear healthier than they were, delaying referrals to specialists and pushing them further down transplant waiting lists. In December 2023, the Organ Procurement and Transplantation Network (OPTN) mandated that every U.S. kidney transplant program submit wait time corrections for Black candidates who had been disadvantaged by this practice.

Now, the first comprehensive analysis of that policy's effects is in. The results, published in JAMA Internal Medicine, show that the correction is associated with meaningful increases in kidney transplant rates for Black patients.

The numbers behind the correction

A research team from Beth Israel Deaconess Medical Center, Brigham and Women's Hospital, and Boston Medical Center analyzed a database of all U.S. kidney transplants performed between January 2022 and June 2025, comparing transplant rates by race and dialysis status before and after the OPTN policy took effect.

Over 21,000 Black transplant candidates received wait time modifications, gaining an average of 1.7 years of priority on the waitlist. That bump in priority translated into real outcomes: among Black candidates, the policy change was associated with an increase of 5.3 transplants per 1,000 listings. Additional analyses showed increased transplant rates among Black patients listed both before and after dialysis initiation.

These are not trivial numbers. In kidney transplantation, where patients can wait years for an organ and many die before one becomes available, 1.7 years of additional priority can mean the difference between receiving a transplant and not.

How a formula created a disparity

The backstory matters. Kidney function is typically estimated using equations that calculate glomerular filtration rate (GFR), a measure of how well the kidneys filter blood. For years, the most widely used equations included a race coefficient that adjusted the estimate upward for Black patients. The rationale was based on population-level differences in muscle mass, but the effect was to systematically overestimate kidney function in Black individuals.

This overestimation had cascading consequences. Patients who appeared to have better kidney function were less likely to be referred to nephrologists, less likely to be evaluated for transplant, and placed on waiting lists later than they should have been. By the time the medical community recognized the problem and removed race from the equations in 2021, years of accumulated disadvantage had already shaped the transplant landscape.

The OPTN policy was designed specifically to remedy that accumulated harm, not just to stop using the biased formula going forward, but to retroactively adjust wait times for patients who had been affected.

Encouraging but incomplete

The researchers are careful to frame the results as a positive signal rather than a solved problem. Rohan Khazanchi, a resident at Brigham and Women's Hospital and Boston Medical Center, noted that Black patients and other marginalized groups are still not transplanted equitably despite being diagnosed with end-stage kidney disease at much higher rates.

Several limitations temper the findings. The study is observational, relying on associations between the policy change and transplant rates rather than a controlled experiment. Variation in how consistently different transplant centers implemented the wait time modifications could influence the results. Some centers may have been more thorough than others in identifying eligible candidates and submitting corrections.

The study also covers a relatively short follow-up period. Whether the initial improvements persist or grow over time remains to be seen. Longer-term data will be needed to determine whether the policy translates into sustained equity gains or represents a one-time correction that fades as the affected cohort moves through the system.

The OPTN policy addresses only one source of disparity: the harm caused by race-based kidney function equations. Other barriers to transplant access for Black patients, including disparities in referral patterns, insurance coverage, living donor availability, and geographic access to transplant centers, remain unaffected by this intervention.

A template for reparative medicine

Senior author Martha Pavlakis, program director of Solid Organ Transplantation at Beth Israel Deaconess Medical Center, described the findings as evidence that guideline and policy changes can translate into real clinical impact. The study offers a rare example of a medical system explicitly attempting to repair harm caused by its own past practices, rather than simply adopting new practices going forward.

Whether this approach can serve as a model for addressing other race-based algorithms in medicine, many of which have been identified and criticized in recent years, is a question that extends well beyond kidney transplantation. But the early evidence suggests that when medical institutions commit to correcting historical errors, measurable benefits can follow.