In this episode of Research Notes, I talk with Dr. Rohan Khazanchi about his recent paper in JAMA Internal Medicine examining what happened when race was removed from equations used to estimate kidney function.For years, these equations overestimated kidney function for Black patients, delaying access to kidney transplant waitlists and reducing the likelihood of receiving a transplant. We discuss how that happened, what changed, and how a national policy attempted to repair the harm by giving patients time back on the waitlist.We also focus on the methods behind the study—specifically why the team used an interrupted time series design to evaluate the policy and why a difference-in-differences approach ultimately didn’t fit the data.Topics covered:-How race became embedded in kidney function equations-Why removing race changed transplant eligibility-The policy that allowed patients to receive time back on the waitlist-Why the team chose interrupted time series over difference-in-differences-What the data showed after the policy was implemented-Who benefited—and who may have been left outKey finding: Patients received a median of about 1.7 years of additional waitlist time—substantial given typical wait times of 3–5 years.