Spirometric classification of chronic obstructive pulmonary disease (COPD)
| Severity | Postbronchodilator FEV1/FVC | FEV1 % pred |
| At risk# | >0.7 | ≥80 |
| Mild COPD | ≤0.7 | ≥80 |
| Moderate COPD | ≤0.7 | 50–80 |
| Severe COPD | ≤0.7 | 30–50 |
| Very severe COPD | ≤0.7 | <30 |
FEV1: forced expiratory volume in one second
FVC: forced vital capacity
#: patients who smoke or have exposure to pollutants, have cough, sputum or dyspnoea