Fig. 2
From: Lung function development after preterm birth in relation to severity of Bronchopulmonary dysplasia
Z-scores presented as median (25th and 75th centiles) for FVC, FEV1 and FEV1/FVC at 7 and 14 years of age in children with no, mild, moderate, severe and all BPD. P-values for comparison of the change from 7 to 14 years in mild, moderate and severe BPD groups compared to the non-BPD group. Nonparametric test for trend across ordered groups comparing mild, moderate and severe BPD to the non-BPD group. P * ≤0.05, ** ≤ 0.01, *** ≤0.001