Characteristic | Overall Population (N = 2514) | Prior Diagnosis of COPD (N = 527) n (%) | No prior diagnosis of COPD (N = 1987) n (%) | p-value* |
---|---|---|---|---|
COPD by Spirometry: |  |  |  | < 0.001 |
 Definite/Probable | 1136 (45.2) | 303 (57.5) | 833 (41.9) |  |
 Uncertain | 107 (4.3) | 54 (10.3) | 53 (2.7) |  |
 None | 1271 (50.6) | 170 (32.2) | 1101 (55.4) |  |
Severity of Spirometry Diagnosis COPD (among definite/probable) |  |  |  | < 0.001 |
 Stage I (Mild) | 456 (40.1) | 71 (23.4) | 385 (46.2) |  |
 Stage II (Moderate) | 583 (51.3) | 173 (57.1) | 410 (49.2) |  |
 Stage III (Severe) | 87 (7.7) | 51 (16.8) | 36 (4.3) |  |
 Stage IV (Very Severe) | 10 (0.9) | 8 (2.6) | 2 (0.2) |  |