Percentages of BO, revealed by acoustic indicators and base-line spirometry (fixed cut-off)
| Groups | Healthy non-smokers | Healthy smokers | BA patients with spirometry negative BO | BA patients with spirometry approved BO |
|---|---|---|---|---|
| FETa | 16 | 27.3 | 41** | 78.9* |
| FETa/C | 17 | 25 | 49.2** | 87.8* |
| FETa/H | 18 | 27.3 | 47.4** | 80.3* |
| FETa/M | 13 | 22.7 | 46.2** | 83* |
| FEV1/FVC >75% | 2.6 | 0 | 0 | 74.6* |
*p<0.001; **p<0.01 re healthy non-smokers.