Lung function variables | Bronchopulmonary dysplasia | p Values (t test) | |
None and mild (n = 53)Mean (95% CI) | Moderate and severe (n = 21)Mean (95% CI) | ||
FEV1 | 89.8 (86.0 to 93.6) | 80.9 (76.2 to 85.7) | 0.004 |
FEF50 | 83.4 (77.8 to 88.9) | 68.1 (56.4 to 79.8) | 0.021 |
TLC | 102.1 (98.1 to 106.2) | 102.4 (97.0 to 107.8) | 0.935 |
RV/TLC | 21.2 (19.6 to 22.8) | 25.3 (22.0 to 28.5) | 0.026 |
Lung function variables are expressed as percentages of predicted, except the ratio RV/TLC. The criteria for classification of bronchopulmonary dysplasia are given in the text.
FEV1, forced expiratory volume in 1 s; FEF50, forced expiratory flow at 50% of forced vital capacity; RV, residual volume; TLC, total lung capacity.