Consistency of reversibility status and clinical outcomes
| Outcome | Consistently* reversible | Consistently* irreversible | p Value adjusted for FEV1 % predicted | p Value adjusted for GOLD stage |
| n | 227 | 1362 | ||
| Subject death | 8 (4%) | 83 (6%) | 0.608 | 0.462 |
| Exacerbation rate | 0.8 (1.1) | 1.3 (1.6) | 0.032 | 0.009 |
| Hospitalised due to COPD exacerbation | 15 (7%) | 206 (15%) | 0.159 | 0.089 |
| Subject withdrawal | 29 (13%) | 186 (14%) | 0.297 | 0.455 |
↵* Consistent = reversible or irreversible according to American Thoracic Society/European Respiratory Society criteria on three of four occasions.
COPD, chronic obstructive pulmonary disease; FEV1, forced expiratory volume in 1 s; GOLD, Global initiative for chronic Obstructive Lung Disease.