We determined how accurately each of the 18 prespecified diagnostic criteria predicted the composite primary outcome of death between 36 weeks’ PMA and 18- to 26-month follow-up (late death) or serious respiratory morbidity, defined as the occurrence of at least one of the following: tracheostomy placed any time before follow-up; continued hospitalization for respiratory reasons at or beyond 50 weeks’ PMA; use of supplemental oxygen, respiratory support, or respiratory monitoring (e.g., pulse oximeter or apnea monitor) at follow-up; or two or more rehospitalizations for respiratory reasons before follow-up. Continued hospitalization at 50 weeks’ PMA is approximately 2 SD above the mean age at discharge for extremely preterm infants included in Neonatal Research Network studies. Two or more rehospitalizations represents the upper 75th percentile for rehospitalization number among Neonatal Research Network babies. Postdischarge respiratory outcome data were ascertained from parents during the follow-up visit. The evaluated respiratory endpoints are consistent with several prior studies exploring postdischarge respiratory morbidity in very preterm infants and represent established adverse outcomes that are meaningful to parents and healthcare providers (2 (link), 18 (link)–22 (link)).
The secondary study outcome was the composite of late death or moderate to severe neurodevelopmental impairment at 18–26 months’ corrected age, assessed by neurologic examination, and defined as a Bayley Scales of Infant and Toddler Development, Third Edition, cognitive or motor composite score less than 85, a Gross Motor Function Classification System level greater than or equal to 2, bilateral blindness, and/or severe hearing impairment that cannot be corrected with amplification (23 , 24 (link)). Growth restriction and measures of healthcare use at follow-up were assessed as additional secondary outcomes.
The secondary study outcome was the composite of late death or moderate to severe neurodevelopmental impairment at 18–26 months’ corrected age, assessed by neurologic examination, and defined as a Bayley Scales of Infant and Toddler Development, Third Edition, cognitive or motor composite score less than 85, a Gross Motor Function Classification System level greater than or equal to 2, bilateral blindness, and/or severe hearing impairment that cannot be corrected with amplification (23 , 24 (link)). Growth restriction and measures of healthcare use at follow-up were assessed as additional secondary outcomes.
