Lung function test results at 16–18 and at 22 years of age and annual change in lung function in 86 subjects who had performed two spirometric tests
| 16–18 years (n=86) | 22 years (n=86) | Annual change | p (annual change) | |
|---|---|---|---|---|
| FEV1=forced expiratory volume in 1 second; VC=vital capacity. | ||||
| *p<0.05, †p<0.01, ‡p<0.001 v 16–18 years (two tailed t test). | ||||
| FEV1 (l) | ||||
| Mean | 4.1 | 4.2 | 0.01 | NS |
| 95% CI | 3.9 to 4.3 | 4.0 to 4.4 | −0.01 to 0.03 | |
| FEV1 (% pred) | ||||
| Mean | 105 | 98‡ | −1.2 | <0.01 |
| 95% CI | 101 to 108 | 95 to 101 | −2.1 to −0.3 | |
| VC (l) | ||||
| Mean | 4.8 | 5.0† | 0.03 | <0.001 |
| 95% CI | 4.6 to 5.1 | 4.8 to 5.3 | 0.01 to 0.06 | |
| VC (% pred) | ||||
| Mean | 109 | 103‡ | −1.5 | <0.001 |
| 95% CI | 106 to 112 | 100 to 106 | −2.0 to −0.9 | |
| FEV1/VC (%) | ||||
| Mean | 85 | 84* | −0.3 | NS |
| 95% CI | 84 to 87 | 82 to 85 | −0.7 to 0.2 | |