Mean (SD) results from delivering profiles A and B five times to each of the four flow measuring devices under identical conditions
| TZ | MS | V | MW | PT | |
|---|---|---|---|---|---|
| TZ=Truzone; MS=MultiSpiro; V=Vitalograph; MW=mini-Wright; PT=pneumotachograph. | |||||
| *Result exceeds ATS accuracy criteria. | |||||
| High flow | |||||
| Profile A | 518.0 (8.4) | 527.0 (13.0) | 525.0 (0) | 520.0 (0) | 521.6 (1.1) |
| Profile B | 746.0 (11.4) | 784.0 (11.4) | 550.0 (0) | 500.0 (0) | 520.0 (2.0) |
| Z=(A+B)/2 | 632.0 (8.9) | 655.5 (18.8) | 537.5 (0) | 510.0 (0) | 520.8 (2.3) |
| B–A | 228.0 (17.9)* | 257.0 (15.7)* | 25.0 (0) | −20.0 (0) | −1.6 (2.3) |
| (B–A)*100/Z | 36.1 (2.8)* | 39.2 (2.5)* | 4.7 (0) | −3.9 (0) | −0.3 (0.4) |
| Low flow | |||||
| Profile A | 188.0 (2.7) | 190.0 (0.0) | 225.0 (0) | 240.0 (0) | 194.4 (0.9) |
| Profile B | 239.0 (2.2) | 191.0 (2.2) | 250.0 (0) | 220.0 (0) | 200.4 (0.5) |
| Z=(A+B)/2 | 213.5 (2.7) | 190.5 (2.2) | 237.5 (0) | 230.0 (0) | 197.4 (1.3) |
| B–A | 51.0 (4.2)* | 1.0 (2.2) | 25.0 (0) | −20.0 (0) | 6.0 (0.7) |
| (B–A)*100/Z | 23.9 (2.0)* | 0.5 (1.2) | 10.5 (0) | −8.7 (0) | 3.0 (0.4) |