Characteristics of subjects
| Complete data set | Incomplete data set# | ||
| Subjects n | Data | ||
| Subjects n | 175 | 75 | |
| Age yrs | 57.4±13.5 | 75 | 56.4±11.8 |
| Pre-BD FEV1/FVC % | 67.0±9.8 | 75 | 67.0±10.3 |
| Pre-BD FEV1 % pred | 80.1±18.4 | 75 | 79.7±21.5 |
| Reversibility % | 8.7±8.8 | 75 | 8.4±8.3 |
| DL,CO/VA¶ % pred | 95.9±15.4 | 75 | 93.4±16.4 |
| FRC % pred | 107.6±23.7 | 65 | 104.2±20.3 |
| Log IgE g·L−1 | 4.3±1.5 | 72 | 4.1±1.7 |
| FeNO ppb | 33.5±26.0 | 5 | 29.8±36.5 |
| Smoking history pack-yrs | 10.8±18.4 | 75 | 10.5±14.8 |
Data are presented as mean±sd, unless otherwise indicated. BD: bronchodilator; FEV1: forced expiratory volume in 1 s; FVC: forced vital capacity; % pred: % predicted; DL,CO: diffusing capacity of the lung for carbon monoxide; VA: alveolar volume; FRC: functional residual capacity; Ig: immunoglobulin; FeNO: exhaled nitric oxide fraction. #: data missing for at least one variable; ¶: adjusted for haemoglobin concentration.