Table 2 Mean for resistance at 5 Hz, resistance at 20 Hz, reactance at 5 Hz, impedance at 5 Hz, and resonant frequency stratified by sex and age
From: Reference values of impulse oscillometry (IOS) for healthy Chinese children aged 4–17 years
IOS parameters | Boy [M(P25–P75)] | Girl [M(P25–P75)] | Z | P |
|---|---|---|---|---|
Preschoolers | ||||
R5, kPa/L/s | 0.88 (0.66–1.12) | 0.83 (0.62–1.09) | − 1.409 | 0.159 |
R20, kPa/L/s | 0.57 (0.41–0.78) | 0.52 (0.39–0.71) | − 2.438 | 0.015 |
X5, kPa/L/s | − 0.29 (− 0.4 to − 0.19) | − 0.29 (− 0.39 to − 0.17) | − 0.682 | 0.495 |
Z5, kPa/L/s | 0.93 (0.70–1.18) | 0.885 (0.67–1.16) | − 1.203 | 0.229 |
R5–R20, kPa/L/s | 0.27 (0.18–0.38) | 0.28 (0.17–0.41) | − 0.229 | 0.819 |
Fres, Hz | 19.44 (17.57–21.33) | 20.03 (17.74–21.94) | − 2.021 | 0.043 |
School-ages | ||||
R5, kPa/L/s | 0.67 (0.49–0.88) | 0.62 (0.45–0.84) | − 3.626 | 0.000 |
R20, kPa/L/s | 0.47 (0.34–0.6125) | 0.42 (0.32–0.59) | − 3.790 | 0.000 |
X5, kPa/L/s | − 0.19 (− 0.27 to − 0.13) | − 0.19 (− 0.27 to − 0.13) | − 0.890 | 0.374 |
Z5, kPa/L/s | 0.70 (0.52–0.92) | 0.65 (0.48–0.88) | − 3.306 | 0.001 |
R5–R20, kPa/L/s | 0.18 (0.11–0.28) | 0.18 (0.11–0.27) | − 0.584 | 0.584 |
Fres, Hz | 17.5 (15.00–19.89) | 17.94 (15.19–19.82) | − 2.803 | 0.005 |
Teenagers | ||||
R5, kPa/L/s | 0.28 (0.24–0.35) | 0.36 (0.31–0.43) | − 9.395 | 0.000 |
R20, kPa/L/s | 0.23 (0.19–0.29) | 0.28 (0.23–0.34) | − 7.505 | 0.000 |
X5, kPa/L/s | − 0.09 (− 0.11 to − 0.07) | − 0.11 (− 0.14 to − 0.09) | − 8.296 | 0.000 |
Z5, kPa/L/s | 0.30 (0.26–0.37) | 0.37 (0.32–0.44) | − 9.659 | 0.000 |
R5–R20, kPa/L/s | 0.06 (0.03–0.09) | 0.08 (0.05–0.12) | − 5.959 | 0.000 |
Fres, Hz | 13.09 (10.31–15.49) | 13.755 (11.08–16.09) | − 2.743 | 0.006 |