TY - JOUR T1 - Interdevice agreement in respiratory resistance values by oscillometry in asthmatic children JF - ERJ Open Research JO - erjor DO - 10.1183/23120541.00138-2018 VL - 5 IS - 1 SP - 00138-2018 AU - Francine M. Ducharme AU - Imane Jroundi AU - Guillaume Jean AU - Guillaume Lavoie Boutin AU - Christiane Lawson AU - Benjamin Vinet Y1 - 2019/02/01 UR - http://openres.ersjournals.com/content/5/1/00138-2018.abstract N2 - Background With several commercially available devices measuring respiratory impedance by oscillometry, the agreement between values obtained on different instruments or frequencies remains unclear. Our aim was to examine the agreement between resistance and reactance parameters on two oscillometry instruments using different waveforms.Methods We conducted a prospective cross-sectional study in asthmatic children aged 3–17 years. Reproducible oscillometry measurements were obtained in random order, by blinded operators, at three modes: 5–10–15–20–25 Hz (5–25 Hz) multifrequency mode on the MasterScreen impulse oscillometry system, and both 5–25 Hz multifrequency mode and 7 Hz monofrequency on the tremoFlo C-100 airwave sinusoidal system. Resistance, reactance and within-breath parameters were examined using the intraclass correlation coefficient (ICC), paired t-test, linear regression and Bland–Altman method.Results Of 50 participants, 44 and 38 completed between-device and within-frequency measurements, respectively. Between-device measurements at 5–25 Hz showed high (ICC 0.88–0.91) and good (ICC 0.69–0.87) agreement in resistance and reactance, respectively, but with an absolute within-patient difference (≥0.05 kPa·L−1·s−1) and proportional bias (≥30% per kPa·L−1·s−1) in all parameters and oscillatory frequencies, apart from resistance at 5 Hz. A significant proportional bias was documented in most within-breath parameters at 5 versus 7 Hz on tremoFlo.Conclusion Observed differences in resistance and reactance suggest the need for instrument- and frequency-specific paediatric normative values.Agreement between forced oscillation values using impulse versus airwave sinusoidal oscillations in children is excellent for resistance at 5 Hz but a proportional bias exists in resistance at ≥10 Hz and reactance, calling for better device harmonisation http://ow.ly/DlNc30nrM5g ER -