Table 3.
Estimates of bSCr and eGFR in healthy community children based on age at enrollment
| Age < 1 years (n = 18) |
Age 1 to < 2 years (n = 46) |
Age 2 to < 5 years (n = 192) |
Age ≥ 5 years (n = 33) |
P value1 | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| bSCr | eGFR | bSCr | eGFR | bSCr | eGFR | bSCr | eGFR | SCr | eGFR | |
| Reference | ||||||||||
| Measured SCr | 0.23 (0.04) | 127.3 (20.8) | 0.25 (0.06) | 135.9 (29.0) | 0.29 (0.07) | 138.2 (30.8) | 0.37 (0.08) | 136.0 (28.7) | < 0.001 | 0.484 |
| SCr estimated by back calculating from an assumed GFR | ||||||||||
| bSCrGFRSchwartz120a | 0.24 (0.01) | 120 (0.0) | 0.27 (0.01) | 120 (0.0) | 0.32 (0.03) | 120 (0.0) | 0.41 (0.04) | 120 (0.0) | < 0.001 | – |
| bSCrGFRPottel120b | 0.23 (0.003) | 126.8 (4.6) | 0.25 (0.01) | 131.9 (5.0) | 0.29 (0.02) | 132.7 (7.0) | 0.39 (0.05) | 126.8 (8.0) | < 0.001 | < 0.001 |
| bSCrGFRSchwartz137a | 0.21 (0.009) | 137 (0.0) | 0.24 (0.01) | 137 (0.0) | 0.28 (0.02) | 137 (0.0) | 0.36 (0.03) | 137 (0.0) | < 0.001 | < 0.001 |
| SCr estimated directly | ||||||||||
| bSCrupperlimitc | 0.39 (0.0) | 73.3 (3.1) | 0.35 (0.0) | 92.9 (4.5) | 0.39 (0.03) | 97.5 (6.8) | 0.54 (0.07) | 90.8 (7.1) | < 0.001 | < 0.001 |
| bSCrCCheightd | 0.23 (0.01) | 125.9 (0.8) | 0.25 (0.01) | 128.4 (0.9) | 0.29 (0.02) | 131.0 (1.4) | 0.36 (0.03) | 134.7 (1.2) | < 0.001 | < 0.001 |
| bSCrCCagee | 0.23 (0.003) | 121.8 (4.5) | 0.25 (0.01) | 128.8 (5.0) | 0.29 (0.02) | 132.5 (7.2) | 0.37 (0.04) | 131.6 (7.2) | < 0.001 | < 0.001 |
1P value calculated using ANOVA to evaluate mean differences across age categories
aBedside Schwartz equation (eGFR = 0.413*height/SCr) used to back calculate creatinine assuming a normal of 120 mL/min/1.73m2 or 137 mL/min/1.73m2 (mean of the community children)
bPottel equation (eGFR = 107.3/(SCr/Q), where Q = 0.0270*age + 0.2329) used to back calculate creatinine assuming a normal of 120 mL/min per 1.73m2
cUpper limit using Ceriotti et al., Clin Chem 2008 54:3
dLinear regression model of height vs. creatinine using healthy community children to estimate baseline creatinine from model
eLinear regression model of age vs. creatinine using healthy community children to estimate baseline creatinine from model