Table 1.
Ventilatory variables measured with the pneumotachograph (PNT) and the non-contact vibrometer using airborne ultrasound (SONAR) during synchronous recordings of the two datasets (PNT-SONAR condition, FRONT recordings).
| SONAR-PNT condition | BF (breath min-1) | TT S | TI S | TE S | VT L | Displacement cm |
|---|---|---|---|---|---|---|
| PNT | 13.2 (11.1–16.8) | 4.6 (3.6–5.5) | 1.7 (1.3–2.0) | 2.8 (2.2–3.4) | 0.7 (0.5–0.8) | – |
| SONAR | 13.1 (11.0–17.1) | 4.6 (3.7–5.5) | 2.0 (1.6–2.5) | 2.6 (2.0–3.1) | – | 3.0 (2.4–4.1) |
| SONAR-PNT condition | CV BF | CV TT | CV TI | CV TE | CV VT | CV displacement |
| PNT | 0.10 (0.08–0.13) | 0.10 (0.09–0.12) | 0.10 (0.08–0.12) | 0.13 (0.11–0.17) | 0.15 (0.11–0.24) | – |
| SONAR | 0.10 (0.08–0.12) | 0.10 (0.08–0.12) | 0.12 (0.10–0.15) | 0.13 (0.10–0.16) | – | 0.17 (0.14–0.21) |
Data are presented as median (Q1–Q3). BF, breathing frequency; TT, breathing cycle period; TI, inspiratory time; TE, expiratory time; VT, tidal volume; s, second; L, liter; CV, coefficient of variation.