β | 95% CI | p Value | |
Variables in the equation | |||
V˙E/V˙O2 (ratio) | 0.423 | 0.18 to 0.67 | 0.001 |
Smoking (non- versus ex- or current smokers) | 0.318 | 0.21 to standardiz ed regression coefficient 1.79 | 0.014 |
Variables not in the equation | |||
Age (y) | 0.229 | — | 0.101 |
DL,CO (% predicted) | −0.098 | — | 0.479 |
FEV1 (% predicted) | −0.107 | — | 0.926 |
FEV1/FVC (% predicted) | −0.021 | — | 0.704 |
P(a-ET) CO2 (mm Hg) | −0.179 | — | 0.172 |
β=standardised regression coefficient.
95% CIs could only be computed for variables included in the final model.