Table 2 Functional characteristics of the 30 CF children

VD, cm³

80 [71; 112]

90 [75; 104]

ND

76 [44; 121]

85 [55; 120]

ND

VD/height, cm²

0.53 [0.46; 0.70]

0.61 [0.55; 0.66]

ND

0.53 [0.37; 0.70]

0.60 [0.41; 0.75]

ND

Spirometry, patients, n

10

7

17

7

FEV₁, L

ND

1.66 [1.14; 2.32]

1.87 [1.38; 2.42]

ND

2.01 [1.56; 2.59]

1.81 [0.97; 2.49]

FEV₁, z-score

ND

 − 2.49 [− 3.51; − 2.09]

 − 2.30 [− 3.47; − 1.80]

ND

 − 0.72 [− 2.41; 0.14]^$

 − 2.38 [− 3.89; − 2.25]

FVC, L

ND

2.33 [1.55; 3.31]

2.38 [1.89; 3.35]

ND

2.73 [1.97; 3.54]

2.51 [1.77; 3.47]

FVC, z-score

ND

 − 1.53 [− 2.66; − 0.35]

 − 1.18 [− 2.34; − 1.11]

ND

 − 0.16 [− 1.52; 0.48]

 − 1.54 [− 2.03; − 0.35]

FEV₁/FVC

ND

0.75 [0.70; 0.77]

0.78 [0.72; 0.79]

ND

0.81 [0.70; 0.83]

0.69 [0.59; 0.76]

FEV₁/FVC, z-score

ND

 − 2.08 [− 2.53; − 1.44]

 − 1.84 [− 2.31; − 1.68]

ND

 − 1.04 [− 2.31; − 0.84]

 − 2.39 [− 3.48; − 1.49]

IOS, patients, n

10

10

10

20

20

20

Fres, Hz

20.97 [14.34; 23.93]

18.82 [13.88; 26.12]

11.9 [11.2; 25.3]

19.21 [13.76; 25.13]

18.99 [14.74; 22.95]

18.3 [14.5; 25.5]

Fres, z-score

0.85 [− 0.70; 1.02]

0.54 [− 0.87; 2.61]

 − 0.90 [− 3.79; 2.35]

0.46 [− 1.01; 1.89]

0.18 [− 0.87; 0.96]

0.17 [− 0.84; 1.12]

R20Hz, kPa/L/s

0.47 [0.31; 0.58]

0.43 [0.28; 0.54]

0.43 [0.29; 0.52]

0.47 [0.39; 0.61]

0.49 [0.39; 0.61]

0.43 [0.33; 0.65]

R20Hz, z-score

1.53 [0.84; 2.25]

1.60 [0.70; 2.18]

1.59 [0.32; 2.00]

1.64 [1.16; 2.68]

1.70 [1.04; 2.42]

1.62 [1.31; 2.37]

R5Hz, kPa/L/s

0.64 [0.38; 0.80]

0.60 [0.37; 0.75]

0.41 [0.35; 0.76]

0.59 [0.45; 0.88]

0.61 [0.46; 0.85]

0.51 [0.42; 1.16]

R5Hz, z-score

1.31 [0.51; 2.35]

1.10 [0.20; 2.56]

0.84 [0.15; 1.69]

1.32 [0.54; 2.46]

1.17 [0.54; 1.85]

1.17 [0.83; 3.77]

R5–20 Hz, kPa/L/s

0.17 [0.06; 0.22]

0.12 [0.05; 0.22]

0.07 [0.02; 0.23]

0.15 [0.07; 0.32]

0.14 [0.06; 0.19]

0.11 [0.07; 0.34]

R5–20 Hz, z-score

0.47 [0.04; 1.70]

0.33 [− 0.32; 1.42]

0.25 [− 0.36; 1.12]

0.55 [− 0.42; 1.57]

0.49 [− 0.49; 0.87]

0.62 [0.30; 2.00]

X5Hz, kPa/L/s

 − 0.24 [− 0.34; − 0.20]

 − 0.23 [− 0.33; − 0.19]

 − 0.16 [− 0.33; − 0.14]

 − 0.19 [− 0.31; − 0.15]

 − 0.20 [− 0.27; − 0.15]

 − 0.16 [− 0.31; − 0.12]

X5Hz, z-score

1.59 [0.58; 2.27]

1.48 [0.87; 1.67]

0.83 [0.67; 1.52]

0.88 [0.06; 1.72]

0.57 [0.16; 1.21]

0.76 [0.45; 2.11]

AX, kPa/L

1.34 [0.73; 2.76]

1.21 [0.68; 2.87]

0.39 [0.35; 2.97]

1.18 [0.50; 2.98]

1.16 [0.58; 2.06]

0.86 [0.41; 3.97]

AX, % z-score

0.92 [0.70; 1.91]

1.25 [0.45; 1.73]

0.84 [0.31; 2.02]

0.82 [0.21; 2.75]

0.76 [0.00; 1.28]

0.90 [0.51; 2.63]

eRIC model

R_centralRS, kPa/L/s

0.49 [0.32; 0.56]

0.44 [0.29; 0.52]

0.42 [0.29; 0.48]

0.49 [0.40; 0.60]

0.50 [0.40; 0.62]

0.41 [0.33; 0.63]

IRS × 100, kPa/L/s²

1.02 [0.90; 1.16]

0.91 [0.88; 1.01]

0.97 [0.90; 1.09]

0.97 [0.76; 1.15]

0.98 [0.75; 1.10]

0.95 [0.80; 1.13]

CpRS × 100, L/kPa

7.83 [5.57; 11.63]

7.15 [5.90; 12.48]

16.14 [5.51; 18.86]

8.80 [4.00; 15.28]

9.44 [7.00; 15.37]

11.05 [4.00; 16.34]

R_peripheralRS, kPa/L/s

0.89 [0.68; 1.04]

0.71 [0.50; 0.94]

0.77 [0.62; 5.00]

1.00 [0.77; 1.67]

1.01 [0.66; 1.05]

0.67 [0.51; 1.14]