Table 2.

Mean value for each measure of GFR as well as the mean difference (±SD and 95% confidence interval) for the difference between each eGFR and the corresponding iohexol GFR

MeasureBaselineDay 100
Mean (± SD; ml/min per 1.73 m2)Mean Difference ± SD (95% CI) between eGFR and iGFReGFR within (%)Mean (± SD; ml/min per 1.73 m2)Mean Difference ± SD (95% CI) between eGFR and iGFReGFR within (%)
30% of GFR10% of GFR30% of GFR10% of GFR
iGFR99.9 (±24.6)86.1 (±28.9)
CKD-EPI84.1 (±21.4)−15.6±19.7 (−21.4 to −9.8)793477.4 (±24.1)−8.0±20.0 (−15.1 to −0.9)8233
Inker CKD-EPI Cr-CysC91.9 (±23.2)−7.9±17.5 (−13.1 to −2.7)893376.4 (±27.1)−8.2±19.2 (−15.1 to −1.3)8416
Inker CKD-EPI CysC98.7 (±28.0)−1.1±23.2 (−7.9 to 5.8)763777.6 (±31.6)−7.1±23.1 (−15.4 to 1.2)7228
Cockroft–Gaulta115.2 (±40.1)15.4±35.2 (5.1 to 25.8)572198.1 (±36.8)12.9±30.1 (2.4 to 23.4)7932
MDRD79.2 (±20.8)−20.6±20.9 (−26.7 to −14.4)702372.7 (±22.9)−12.7±20.3 (−19.9 to −5.5)7630
iGFR DBS100.0 (±26.4)0.0±15.2 (−4.5 to 4.5)984692.0 (±35.7)5.9±13.9 (0.8 to 10.9)9734
  • Percentages of eGFR measurements that are within 30% and 10% of the corresponding iGFR are also presented. Results are presented separately for baseline and day 100 pairs. Percentage of eGFR within iGFR was statistically significant (P<0.05) only at baseline for Inker CKD-EPI Cr-CysC versus Inker CKD-EPI CysC (P=0.03), Inker CKD-EPI Cr-CysC versus Cockroft–Gault (P=0.003), and Inker CKD-EPI Cr-CysC versus MDRD (P=0.02); no statistical comparisons were made with iGFR DBS. iGFR, iohexol GFR; CKD-EPI, CKD Epidemiology Collaboration; Cr, creatinine; CysC, cystatin C; MDRD, Modification of Diet in Renal Disease; DBS, dried blood spot; 95% CI, 95% confidence interval.

  • a Units are milliliters per minute.