Main anthropometric and lung function data
| Random control | Spirometry with FEV1 >20% | BRONCUS trial | |
| Patients n | 243 | 208 | 523 |
| Spirometries | 314 | 345 | 5042 |
| Sex M/F | 187/56 | 171/37 | 413/110 |
| Smokers former or current/non | 143/100 | 102/106 | 284/239 |
| Age yr | 62±7 | 62±8 | 63±8 |
| FEV1 % pred | 53±10 | 52±9 | 53±9 |
Data presented as n or mean±sd unless otherwise stated. M: male; F: female; FEV1 % pred: forced expiratory flow in one second percentage predicted; BRONCHUS: Bronchitis Randomized on N-acetylcysteine (NAC) Cost-Utility Study.