Simple linear regression model without interactions for predicting square root AEX-FV
| Term | Estimate | SE | T ratio | Prob >|T| | VIF | Main effect | R2 | RASE |
| Intercept | −0.070 | 0.007 | −10.027 | <0.0001 | – | – | T: 0.993 | T: 0.078 |
| FVC | 0.501 | 0.002 | 218.464 | <0.0001 | 2.48 | 0.24 | ||
| PEF | 0.062 | 0.002 | 37.790 | <0.0001 | 5.24 | 0.21 | ||
| FEF25 | 0.097 | 0.002 | 51.527 | <0.0001 | 5.88 | 0.20 | V: 0.993 | V: 0.077 |
| FEF50 | 0.118 | 0.002 | 47.515 | <0.0001 | 4.98 | 0.19 | ||
| FEF75 | 0.168 | 0.005 | 35.138 | <0.0001 | 3.19 | 0.16 |
In both training (T, n=2577) and validation (V, n=1057) sets, model’s R2 was 0.993 and RASE was 0.078–0.077.
AEX-FV, area under expiratory flow-volume curve; FEF25, forced expiratory flow at 25%; FVC, forced vital capacity; PEF, peak expiratory flow; RASE, root average square error; VIF, variance inflation factor.