Bias with estimated GFR (eGFR) by age (years). Bias with estimated GFR (eGFR) by age (years). Mean percentage bias (eGFR − mGFR)/mGFR (Panel A) and mean bias calculated for log eGFR − log mGFR (Panel B) are both depicted. The CKD-EPI equation is represented by the solid smoother curves (lambda = 1000,000), and the MDRD equation is represented by the dashed smoother curves. Native CKD and transplant recipients (n = 4558) are represented by the black curves, and the potential kidney donors and postnephrectomy kidney donors (n = 680) are represented by the gray curves. Kazunori Murata et al. CJASN 2011;6:1963-1972 ©2011 by American Society of Nephrology