Infants who were born at >34 weeks' gestation (near- or full-term) were enrolled when they required assisted ventilation and had an oxygenation index (OI) >15 and <25 on any 2 measurements in a 12-hour interval. Infants were randomized to receive either early iNO or to simulated initiation of iNO (control). Infants who had an increase in OI to 25 or more were given iNO as standard therapy. The neurodevelopment of the subjects were evaluated at 18-22 months corrected age.