The equation used by egfr() with method = "CKDEPI 2021".
Details
The CKD-EPI 2021 creatinine equation (race-free): $$eGFR = 142 \cdot \min(S_{cr}/\kappa, 1)^\alpha \cdot \max(S_{cr}/\kappa, 1)^{-1.2} \cdot 0.9938^A \cdot 1.012^F$$
where:
\(S_{cr}\) = serum creatinine (mg/dL)
\(\kappa\) = 0.7 (female) or 0.9 (male)
\(\alpha\) = -0.241 (female) or -0.302 (male)
\(A\) = age (years)
\(F\) = 1 (female) or 0 (male)