Proportional odds model of factors associated with neurodevelopmental disability.

*Estimated odds ratios from proportional odds model; odds of mild or severe disability versus no disability, and odds of severe disability versus milder or no disability; Score test for the proportional odds assumption: p = 0.149; Likelihood ratio test for overall model significance: p<0.001. §The model was first run with No BPD as the reference category. In order to obtain estimates for BPD with chronic oxygen dependency versus BPD, the model was run a second time, using BPD as the reference category. BPD: bronchopulmonary dysplasia; NEC: necrotizing enterocolitis; IVH: intraventricular hemorrhage; SGA: small for gestational age; PDA: patent ductus arteriosus; RDS: respiratory distress syndrome; ROP: retinopathy of prematurity.