Fig. 1: Schematic description of study population.

The study population included 178 (57%) of infants with histopathologically confirmed NEC (n = 143) and SIP (n = 35). Cases of NEC or SIP were classified by outcome (surgical or autopsy). “Other” exclusions consisted of ileal strictures, omphalocele, and abdominal hernia. NICU neonatal intensive care unit, NEC necrotizing enterocolitis, SIP spontaneous intestinal perforation, GIFA Gastrointestinal FilmArray.