Table 2.

Creatinine-based equations developed in the AASK, MDRD, and CKD-EPI trials

Six-variable MDRD study equation
    GFR (ml/min per 1.73 m2) = 170 × SCr (mg/dl)−0.999 × age−0.176 × 0.762 (if woman) × BUN (mg/dl)−0.170 × albumin+0.318 × 1.18 for African American
Four-variable MDRD study equation
    GFR (ml/min per 1.73 m2) = 186 × SCr (mg/dl)−1.154 × age−0.203 × 0.742 (if woman) × 1.21 for African American
Six-variable AASK study equation
    GFR (ml/min per 1.73 m2) = 222 × SCr (mg/dl)−0.974 × age−0.267 × 0.757 (if woman) × BUN (mg/dl)−0.108 × albumin+0.372
Four-variable AASK study equation
    GFR (ml/min per 1.73 m2) = 329 × SCr (mg/dl)−1.096 × age−0.294 × 0.736 (if woman)
Four-variable MDRD study equation (IDMS traceable)
    GFR (ml/min per 1.73 m2) = 175 × SCr (mg/dl) −1.154 × age−0.203 × 0.742 (if woman) × 1.21 for African American
CKD-EPI study equation
    African American female
        serum creatinine <0.7 mg/dl
            GFR (ml/min per 1.73 m2) = 166 × (SCr/0.7)−0.329 × 0.993age
        serum creatinine >0.7 mg/dl
            GFR (ml/min per 1.73 m2) = 166 × (SCr/0.7)−1.209 × 0.993age
    African American male
        serum creatinine <0.9 mg/dl
            GFR (ml/min per 1.73 m2) = 163 × (SCr/0.9)−0.411 × 0.993age
        serum creatinine >0.7 mg/dl
            GFR (ml/min per 1.73 m2) = 163 × (SCr/0.9)−1.209 × 0.993age
    Caucasian female
        serum creatinine <0.7 mg/dl
            GFR (ml/min per 1.73 m2) = 144 × (SCr/0.7)−0.329 × 0.993age
        serum creatinine >0.7 mg/dl
            GFR (ml/min per 1.73 m2) = 144 × (SCr/0.7)−1.209 × 0.993age
    Caucasian male
        serum creatinine <0.9 mg/dl
            GFR (ml/min per 1.73 m2) = 141 × (SCr/0.9)−0.411 × 0.993age
        serum creatinine >0.7 mg/dl
            GFR (ml/min per 1.73 m2) = 141 × (SCr/0.9)−1.209 × 0.993age
  • SCr, serum creatinine; BUN, blood urea nitrogen; CKD-EPI, Chronic Kidney Disease Epidemiology Collaboration; IDMS, Isotope Dilution Mass Spectrometry.