Differential classification of infants in United States neonatal intensive care units for weight, length, and head circumference by United States and international growth curves
Analytics and Data Science Institute
© 2020 Informa UK Limited, trading as Taylor & Francis Group. Background: Clinicians and researchers use a variety of intrauterine growth curves to classify NICU infants as small (SGA), appropriate (AGA), or large for gestational age (LGA). Since curve creation methods and samples vary, SGA/AGA/LGA cut-offs and resulting subgroups of infants vary among curves and impact outcome study findings - limiting generalisability. Aim: Determine how two international and two US-specific curves classified US NICU infants. Subjects and methods: Classified 192,888 infants from US NICUs (2013–2016) as SGA or LGA for birthweight, length, and head circumference, using the international Fenton and INTERGROWTH-21st curves and US-specific Olsen and Lubchenco (historical) curves. Results: Modern curves classified approximately 10% of infants as SGA up to 32 weeks, but older infants had increased variability. The INTERGROWTH-21st curves consistently had rates above 10% for LGA after 32 weeks. Conclusions: While Olsen and Fenton both fit, the Olsen curves had overall best-fit for our sample of US NICU infants. The INTERGROWTH-21st curves fit the definitions for SGA and LGA for younger ages, but inferences outside of these definitions are unwarranted due to limited sample size. The INTERGROWTH-21st sample used for 33 weeks and older infants was physically smaller at the upper percentiles than our sample of US infants.
Annals of Human Biology
Digital Object Identifier (DOI)
Ferguson, A. Nicole; Olsen, Irene E.; Clark, Reese H.; Yockey, Bryan D.; Boardman, Jonathan; Biron, Kyle; Jannuzzo, Cooper; Waskiewicz, Daniel; Mendoza, Amanda; and Lawson, M. Louise, "Differential classification of infants in United States neonatal intensive care units for weight, length, and head circumference by United States and international growth curves" (2020). Faculty Publications. 4671.