Fig. 2

Subject enrollment, data collection and adverse prognosis evaluation at each follow-up time point. VPI: Very preterm infant, VLBWI: Very low birth weight infant, BPD: Bronchopulmonary dysplasia, ROP: Retinopathy, NEC: Necrotizing enterocolitis, IVH: Intraventricular hemorrhage, CH: Congenital hypothyroidism