Figure 1.

Directed acyclic graph depicting the relationship between perinatal and postnatal factors, physiological instability and systemic inflammation, patent ductus arteriosus ligation and neonatal and neurodevelopmental outcomes (ACS – Antenatal corticosteroids, CLD – Chronic lung disease; GA – Gestational age, ROP – Retinopathy of prematurity, PDA – Patent ductus arteriosus)