Ability of change in a spirometric variable following salbutamol inhalation to discriminate between children with asthma and healthy children
| Spirometry | Area | Threshold (%) | Sensitivity (%) | Specificity (%) | PPV (%) | NPV (%) |
|---|---|---|---|---|---|---|
| FVC | 0.51 | 5 | 50.0 | 71.3 | 54.4 | 67.5 |
| FEV1 | 0.66 | 7 | 49.1 | 81.0 | 34.4 | 88.7 |
| FEV0.75 | 0.70 | 11 | 51.2 | 88.4 | 47.1 | 89.0 |
| FEV0.5 | 0.66 | 12 | 52.3 | 78.2 | 32.7 | 89.0 |
Area, area under the receiver operating characteristic curve; NPV, negative predictive value for excluding asthma; PPV, positive predictive value for detecting asthma; threshold, value of a spirometric variable giving the best balance between sensitivity and specificity.