Participants
Children were identified from local neonatal follow-up databases at the respective study sites and consent/assent was obtained by the research coordinator. Children were eligible if they were 7-9 years of age and born at less than 28 weeks’ gestation, with and without history of BPD, and were enrolled in the PICTURE study13. Participants were ineligible if they had 1) known lung anomalies or genetic conditions which may affect pulmonary function or MRI findings 2) contraindications for MRI, 3) any severe neurosensory impairment which might prevent test completion, or 4) a recent bacterial/viral respiratory illness (within the preceding 6 weeks)13.