Logistic regression analysis of association between neonatal morbidity and disability at two years of age.

*paIntraventricular hemorrhage grade 3 or more and/or cystic periventricular leukomalacia.bSymptomatic patent ductus arteriosus which required treatment.cIncluding: retinopathy grade 3 or more, necrotizing enterocolitis, bronchopulmonary dysplasia, intraventricular hemorrhage grade 3 or more, cystic periventricular leukomalacia.dRetinopathy of prematurity grade 3 or more and/or bronchopulmonary dysplasia and/or severe brain injury.