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Description of phenotypic definitions for COPD
| COPD definitiona | n (%) |
|---|---|
| Spirometry | 72 (72) |
| FEV1 and FEV1/FVC | 49 (68) |
| FEV1 only | 12 (17) |
| FEV1/FVC only | 8 (11) |
| Not stated | 3 (4) |
| Emphysema | 6 (6) |
| Chronic bronchitis | 6 (6) |
| Not stated | 16 (16) |
aEmphysema definitions may also include spirometry. By our study definition, chronic bronchitis also includes evidence of obstruction.
