Mean (SE) demographic and pulmonary function characteristics of subject groups
| Parameter | Group I, age 19–36 (n = 19) | Group II, age 64–83 (n = 15) |
|---|---|---|
| Age | 27 (1) | 71 (1) |
| Sex (F:M) | 7:12 | 8:7 |
| FEV1 | 109 (2) | 110 (3) |
| FVC | 106 (2) | 99 (3) |
| FEV1/FVC | 82 (1) | 70 (1) |
| FEF25–75 | 106 (4) | 97 (7) |
FEV1 = forced expiratory volume in one second as percentage of normal predicted value; FVC = forced vital capacity as percentage of normal predicted value; FEV1/FVC = ratio of FEV1 to FVC; FEF25–75 = mean forced expiratory flow from 25% to 75% of FVC as percentage of predicted value.