Directed Acyclic Graph Summarizing Assumed Causal Structure
BPD
BRONCHOPULMONARY DYSPLASIA
BPD indicates bronchopulmonary dysplasia; DHA, docosahexaenoic acid.Owing to the blinded nature of the original trial, proposed confounders in the causal diagram and BPD at 36 weeks’ postmenstrual age were ascertained in a fully blinded manner. The trial statistical team (T.R.S. and J.M.B.) and 9 parents representing 11 children (5 children in the DHA group and 6 children in the control group) were unblinded after the analysis of BPD data. Except for these individuals, all participants, study personnel, and outcome assessors remained blinded to group allocation through completion of the IQ assessments at 5 years’ corrected age.