Introduction
Calculations and methodsa
| Formulab
|
---|---|
Calculation of reference GFR (GFR7p) | |
Absolute GFR7p (mL/min) [5] | GFR = Cl = I/(expA/α + expB/β) |
BSA normalized GFR7p (mL/min/1.73 m2) | ClBSA = Cl × 1.73/BSA |
Calculations of 2-point GFR (GFR2p) | |
Cl1
| Cl1 = I/ expA/α |
BSA normalized Cl1
| Cl1,BSA = Cl1 × 1.73/BSA |
BMadultafter (original)c [14] | Cl = 0.9908 × Cl1 – 0.001218 × Cl1
2
|
ClBSA = Cl × 1.73/BSA | |
BMadultbefore (adapted) | ClBSA = 0.9908 × Cl1,BSA − 0.001218 × Cl1,BSA
2
|
BMchildbefore (original)d [15] | ClBSA = 1.01 × Cl1, BSA − 0.0017 × Cl1, BSA
2
|
BMchildafter (adapted) | Cl = 1.01 × Cl1 – 0.0017 × Cl1
2
|
ClBSA = Cl × 1.73/BSA | |
BMcombbefore (original)e [17] | ClBSA = 1.0004 × Cl1,BSA – 0.00146 × Cl1, BSA
2
|
BMcombafter (adapted) | Cl = 1.0004 × Cl1 − 0.00146 × Cl1
2
|
ClBSA = Cl × 1.73/BSA | |
Flembefore (original)e [12] | ClBSA = Cl1,BSA /[1 + 0.0017 × Cl1,BSA] |
Flemafter (adapted) | Cl = Cl1 /[1 + 0.0017 × Cl1] |
ClBSA = Cl × 1.73/BSA | |
JBMbefore (original)e [23] | ClBSA = Cl1,BSA /1 + fBSA × Cl1,BSA
|
fBSA = 0.00185BSA−0,3
| |
JBMafter (original)e [23] | Cl = Cl1 /1 + f × Cl1
|
f = 0.0032BSA−1.3
| |
ClBSA = Cl × 1.73/BSA | |
SAMbefore (original)d [6] | ClBSA = 1.0019 × Cl1,BSA − 0.001258 × Cl1, BSA
2
|
SAMafter (adapted) | Cl = 1.0019 × Cl1 − 0.001258 × Cl1
2
|
ClBSA = Cl × 1.73/BSA | |
NSMbefore (original)e [24] | ClBSA = Cl1,BSA /[1 + 0.0012 × Cl1,BSA/100] |
NSMafter (adapted) | Cl = Cl1 /[1 + 0.0012 × Cl1/100] |
ClBSA = Cl × 1.73/BSA |
Patients and methods
Patients
Methods
Calculations and statistics
Results
Formulaa
| Sampling schemes (h) | Mean bias (95 % CI) (mL/min/1.73 m2) | 95 % Limits of agreement (mL/min/1.73 m2) |
R
| P5 (%)b
| P10 (%)b
| P15 (%)b
| 95 Percentile of deviations (90 % CI) (%)c
|
---|---|---|---|---|---|---|---|---|
BMadultbefore
| 2 and 3 | −0.05 (−1.10 to 1.00) | −10.2 to 10.1 | 0.9877 | 60.4 | 79.2 | 89.6 | 26.4 (16.5–64.9) |
BMadultbefore
| 2 and 4 | 0.30 (−0.60 to 1.19) | −8.4 to 8.9 | 0.9911 | 67.7 | 87.5 | 95.8 | 14.12 (11.7–18.5) |
BMadultbefore
| 2 and 5 | −0.20 (−0.70 to 1.09) | −8.5 to 8.9 | 0.9910 | 78.1 | 92.7 | 97.9 | 12.4 (8.9–17.0) |
BMadultbefore
| 3 and 5 | 1.07 (−0.16 to 2.31) | −10.9 to 13.0 | 0.9840 | 56.3 | 86.5 | 95.8 | 15.2 (11.7–18.7) |
Flembefore
| 2 and 3 | −0.94 (−1.99 to 0.11) | −11.1 to 9.2 | 0.9877 | 59.4 | 82.3 | 89.6 | 25.8 (16.6–50.0) |
Flembefore
| 2 and 4 | −0.60 (−1.50 to 0.30) | −9.3 to 8.1 | 0.9911 | 70.8 | 88.5 | 95.8 | 13.7 (10.8–22.8) |
Flembefore
| 2 and 5 | −0.69 (−1.59 to 0.21) | −9.4 to 8.0 | 0.9911 | 77.1 | 92.7 | 97.9 | 10.6 (9.8–16.1) |
Flembefore
| 3 and 5 | 0.19 (−1.04 to 1.41) | −11.6 to12.0 | 0.9837 | 63.5 | 86.5 | 95.8 | 14.4 (11.7–17.0) |
JBM | 2 and 3 | −1.82 (−2.87 to −0.76) | −12.0 to 8.4 | 0.9879 | 56.3 | 82.3 | 89.6 | 25.5 (16.7–64.7) |
JBM | 2 and 4 | −1.46 (−2.38 to −0.55) | −10.3 to 7.4 | 0.9913 | 64.6 | 89.6 | 96.9 | 14.1 (11.0–20.4) |
JBM | 2 and 5 | −1.69 (−2.57 to −0.82) | −10.1 to 6.8 | 0.9919 | 74.0 | 95.8 | 99.0 | 9.8 (7.6–11.2) |
JBM | 3 and 5 | −0.72 (−1.92 to 0.48) | −12.3 to 10.9 | 0.9840 | 63.5 | 88.5 | 95.8 | 14.6 (11.7–17.1) |
Formulaa
| Mean bias (95 % CI) (mL/min/1.73 m2) | 95 % limits of agreement (mL/min/1.73 m2) |
R
| P5 (%)b
| P10 (%)b
| P15 (%)b
| 95 Percentile of deviations (90 % CI) (%)c
|
---|---|---|---|---|---|---|---|
BMadultafter
| 3.70 (2.38 to 5.02) | −9.1 to 16.5 | 0.9848 | 57.3 | 82.3 | 88.5 | 20.4 (16.3–24.5) |
BMadultbefore
| 0.20 (−0.70 to 1.09) | −8.5 to 8.9 | 0.9910 | 78.1 | 92.7 | 97.9 | 12.4 (8.9–17.0) |
BMchildbefore
| −2.02 (−3.07 to −0.97) | −12.2 to 8.2 | 0.9900 | 77.1 | 89.6 | 96.9 | 11.9 (10.9–16.2) |
BMcombbefore
| −0.92 (−1.86 to 0.02) | −10.0 to 8.2 | 0.9907 | 78.1 | 91.7 | 97.9 | 11.3 (9.2–16.5) |
Flembefore
| −0.69 (−1.59 to 0.21) | −9.4 to 8.0 | 0.9911 | 77.1 | 92.7 | 97.9 | 10.6 (9.8–16.1) |
JBM | −1.69 (−2.57 to −0.82) | −10.1 to 6.8 | 0.9919 | 74.0 | 95.8 | 99.0 | 9.8 (7.6–11.2) |
SAMbefore
| 0.75 (−0.16 to 1.65) | −8.0 to 9.5 | 0.9910 | 77.1 | 92.7 | 97.9 | 13.2 (9.7–16.3) |
NSMbefore
| 2.15 (1.17 to 3.12) | −7.3 to 11.6 | 0.9910 | 72.9 | 88.5 | 94.8 | 15.4 (12.5–16.8) |
Patient groups |
N
| Method | Mean bias (95 % CI) (mL/min/1.73 m2) | 95 % limits of agreement (mL/min/1.73 m2) |
R
| P5 (%)a
| P10 (%)a
| P15 (%)a
| 95 percentile of deviations (90 % CI) (%)b
|
---|---|---|---|---|---|---|---|---|---|
All participants | 96 | BMadultbefore
| 0.20 (−0.70 to 1.09) | −8.5 to 8.9 | 0.9910 | 78.1 | 92.7 | 97.9 | 12.4 (8.9–17.0) |
BMchildbefore
| −2.02 (−3.07 to −0.97) | −12.2 to 8.2 | 0.9900 | 77.1 | 89.6 | 96.9 | 11.9 (10.9–16.2) | ||
Flembefore
| −0.69 (−1.59 to 0.21) | −9.4 to 8.0 | 0.9911 | 77.1 | 92.7 | 97.9 | 10.6 (9.8–16.1) | ||
JBM | −1.69 (−2.57 to −0.82) | −10.1 to 6.8 | 0.9919 | 74.0 | 95.8 | 99.0 | 9.8 (7.6–11.2) | ||
Age <6 years | 33 | BMadultbefore
| 1.13 (−0.34 to 2.61) | −7.0 to 9.3 | 0.9909 | 69.7 | 87.9 | 100 | 12.8 (9.7–13.4) |
BMchildbefore
| −0.94 (−2.38 to 0.51) | −8.9 to 7.1 | 0.9914 | 75.8 | 90.9 | 100 | 11.1 (9.8–11.6) | ||
Flembefore
| −1.01 (−2.93 to 0.93) | −11.7 to 9.7 | 0.9870 | 69.7 | 87.9 | 97.0 | 13.1 (10.0–18.4) | ||
JBM | −2.00 (−3.62 to −0.39) | −10.9 to 6.9 | 0.9888 | 51.5 | 93.9 | 100 | 11.7 (8.0–14.0) | ||
Age <10 years | 52 | BMadultbefore
| 0.88 (−0.48 to 2.23) | −8.7 to 10.4 | 0.9973 | 71.2 | 88.5 | 96.2 | 14.6 (11.3–17.9) |
BMchildbefore
| −1.22 (−2.59 to 0.14) | −10.8 to 8.4 | 0.9879 | 76.9 | 90.4 | 96.2 | 12.9 (10.1–20.2) | ||
Flembefore
| −0.72 (−2.10 to 0.66) | −10.4 to 9.0 | 0.9892 | 71.2 | 90.4 | 96.2 | 12.7 (9.8–18.4) | ||
JBM | −1.99 (−3.35 to −0.63) | −11.6 to 7.6 | 0.9873 | 61.5 | 94.2 | 98.1 | 11.9 (7.8–19.2) | ||
Age ≥10 years | 44 | BMadultbefore
| −0.61 (−1.75 to 0.53) | −8.0 to 6.7 | 0.9948 | 86.4 | 97.7 | 100 | 8.8 (7.1–12.3) |
BMchildbefore
| −2.96 (−4.62 to -1.31) | −13.6 to 7.7 | 0.9930 | 77.3 | 88.6 | 97.7 | 12.2 (10.1–16.2) | ||
Flembefore
| −0.67 (−1.82 to 0.49) | −8.1 to 6.8 | 0.9934 | 84.1 | 95.5 | 100 | 10.2 (7.3–11.6) | ||
JBM | −1.34 (−2.4 to −0.26) | −8.3 to 5.6 | 0.9957 | 88.6 | 97.7 | 100 | 9.63 (5.8–10.7) | ||
BSA <0.5 m2
| 11 | BMadultbefore
| 0.32 (−2.23 to 2.87) | −7.1 to 7.8 | 0.9938 | 63.6 | 90.9 | 100 | NA |
BMchildbefore
| 0.98 (−2.49 to 4.45) | −9.1 to 11.1 | 0.9911 | 72.7 | 81.8 | 100 | NA | ||
Flembefore
| −0.35 (−3.01 to 2.32) | −8.1 to 7.4 | 0.9939 | 72.7 | 90.9 | 100 | NA | ||
JBM | −2.67 (−6.42 to 1.07) | −13.6 to 8.2 | 0.9921 | 45.5 | 90.9 | 100 | NA | ||
BSA <1.0 m2
| 47 | BMadultbefore
| 1.31 (0.09–2.53) | −6.8 to 9.4 | 0.9915 | 72.3 | 89.4 | 97.9 | 13.0 (10.54–17.9) |
BMchildbefore
| −0.66 (−1.82 to 0.50) | −8.4 to 7.1 | 0.9919 | 78.7 | 91.5 | 97.9 | 11.3 (9.6–15.2) | ||
Flembefore
| 0.42 (−0.77 to 1.60) | −7.5 to 8.3 | 0.9914 | 74.5 | 91.5 | 97.9 | 11.3 (9.2–16.1) | ||
JBM | −1.69 (−2.90 to −0.48) | −9.7 to 6.4 | 0.9910 | 61.7 | 95.7 | 100 | 9.9 (7.6–14.0) | ||
BSA <1.45 m2
| 77 | BMadultbefore
| 0.59 (−0.44 to 1.62) | −8.3 to 9.5 | 0.9894 | 75.3 | 90.9 | 97.4 | 12.7 (9.3–17.01) |
BMchildbefore
| −1.44 (−2.51 to −0.37) | −10.7 to 7.8 | 0.9895 | 77.9 | 90.9 | 97.4 | 11.7 (9.8 – 15.7) | ||
Flembefore
| −0.29 (−1.31 to 0.73) | −9.1 to 8.6 | 0.9893 | 76.6 | 92.2 | 97.4 | 11.0 (9.7–16.4) | ||
JBM | −1.70 (−2.73 to −0.68) | −10.6 to7.2 | 0.9895 | 70.1 | 94.8 | 98.7 | 10.7 (7.8–14.5) | ||
GFR 30 mL/min/1.73 m2
| 18 | BMadultbefore
| −0.28 (−0.60 to 0.04) | −1.5 to 1.0 | 0.9960 | 94.4 | 100 | 100 | NA |
BMchildbefore
| −0.11 (−0.43–0.20) | −1.4 to 1.1 | 0.9960 | 94.4 | 100 | 100 | NA | ||
Flembefore
| −3.00 (−0.63 to 0.03) | −1.6 to 0.99 | 0.9960 | 94.4 | 100 | 100 | NA | ||
JBM | −0.36 (−0.69 to −0.03) | −1.7 to 1.0 | 0.9959 | 88.9 | 100 | 100 | NA | ||
GFR 30–59 mL/min/1.73 m2
| 23 | BMadultbefore
| 0.21 (−0.40 to 0.83) | −2.6 to 3.0 | 0.9836 | 91.3 | 95.7 | 100 | 10.2 (4.7–11.3) |
BMchildbefore
| 0.01 (−0.60 to 0.62) | −2.8 to 2.8 | 0.9835 | 91.3 | 95.7 | 100 | 9.9 (4.6–10.9) | ||
Flembefore
| −0.15 (−0.76 to 0.46) | −2.9 to 2.6 | 0.9835 | 91.3 | 95.7 | 100 | 9.4 (4.5–10.4) | ||
JBM | −0.65 (−1.30 to 0.01) | −3.6 to 2.3 | 0.9817 | 87.0 | 100 | 100 | 7.6 (5.6–8.0) | ||
GFR 60 to <90 mL/min/1.73 m2
| 27 | BMadultbefore
| 0.90 (−0.62 to 2.43) | −6.6 to 8.4 | 0.9284 | 77.8 | 88.9 | 96.3 | 16.1 (9.9–17.9) |
BMchildbefore
| −1.18 (−2.75 to 0.39) | −9.0 to 6.6 | 0.9284 | 74.1 | 92.6 | 96.3 | 13.5 (9.0–15.2) | ||
Flembefore
| −0.28 (−1.81 to 1.25) | −7.9 to 7.3 | 0.9284 | 77.8 | 88.9 | 96.3 | 14.3 (9.3–16.1) | ||
JBM | −1.83 (−3.11 to −0.55) | −8.2 to 4.5 | 0.9498 | 66.7 | 96.3 | 100 | 9.4 (7.1–10–7) | ||
GFR ≥ 90 mL/min/1.73 m2
| 28 | BMadultbefore
| −0.20 (−3.00 to 2.61) | −14.4 to 14.0 | 0.8890 | 57.1 | 89.3 | 96.4 | 14.9 (10.3–17.0) |
BMchildbefore
| −5.73 (−8.66 to −2.79) | −20.6 to 9.1 | 0.8824 | 57.1 | 75.0 | 92.9 | 18.4 (11.8–20.2) | ||
Flembefore
| −1.78 (−4.56 to 0.99) | −15.8 to 12.2 | 0.8914 | 53.6 | 89.3 | 96.4 | 14.8 (9.8–18.4) | ||
JBM | −3.28 (−5.98 to 0.57) | −16.9 to 10.4 | 0.8995 | 60.7 | 89.3 | 96.4 | 16.9 (9.7–19.2) |