Table 2.

Adjusted hierarchical logistic regression analysis^* (adjusted odds ratios, 95% confidence intervals)

	Model 11	Model 22	Model 33
BPD or death prior to 36wk PMA	1.58 [1.29,1.93]	1.70 [1.35,2.14]	0.96 [0.76,1.21]
BPD among survivors to 36 wk PMA	1.42 [1.14,1.76]	1.59 [1.25,2.00]	0.86 [0.67,1.09]
Death prior to 36wk PMA	2.79 [1.98,3.92]	3.42 [2.18,5.38]	3.01 [1.59,5.71]

^*Robust sandwich variance estimator for cluster-correlated data used in all models to relax assumption of independence among babies cared for in same center

¹Unadjusted bivariable analysis

²Adjusted for gestational age, birthweight, sex, race/ethnicity, prenatal steroids, chorioamnionitis, gestational hypertension or pre/eclampsia, gestational diabetes, mode of delivery, small for gestational age, and exclusive human milk feeding

³Adjusted for same variables as model 2 plus treatment with caffeine, surfactant, mechanical ventilation on the first day of life, and the total duration (days) of mechanical ventilation during the first week of life

PMA (postmenstrual age); BPD (bronchopulmonary dysplasia); wk (weeks)