Table 5.

Bias, precision, and accuracy of creatinine and cystatin C estimatesa

BiasPrecisionAccuracy % Within
Measured values
    creatinine clearance3.816.83274
Estimates using creatinine
    abbreviated MDRD−10.013.12474
    original MDRD−11.512.21869
Estimates using cystatin C
    Le Bricon−3.811.84289
  • a Bias was defined as the mean difference between measured (99Tc-DTPA) and estimated GFR; precision was defined as the SD of the difference between measured (99Tc-DTPA) and estimated GFR. Both precision and bias were expressed as ml/min per 1.73 m2; accuracy was defined as the proportion of values that were within 10 or 30% of the measured (99Tc-DTPA) GFR.