Department of Statistics and Analytical Sciences, Kennesaw State University, Kennesaw, GA, USA.
Department of Nutrition Sciences, College of Nursing and Health Professions, Drexel University, Philadelphia, PA, USA.
Ann Hum Biol. 2020 Sep;47(6):564-571. doi: 10.1080/03014460.2020.1817555. Epub 2020 Sep 18.
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.
Determine how two international and two US-specific curves classified US NICU infants.
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.
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.
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.
临床医生和研究人员使用各种宫内生长曲线将新生儿重症监护病房（NICU）的婴儿分为小（SGA）、适当（AGA）或大于胎龄（LGA）。由于曲线创建方法和样本不同，SGA/AGA/LGA 截止值和由此产生的婴儿亚组在不同的曲线之间存在差异，并影响结果研究发现-限制了普遍性。
确定两种国际和两种美国特定曲线如何对美国 NICU 婴儿进行分类。
使用国际 Fenton 和 INTERGROWTH-21 曲线以及美国特定的 Olsen 和 Lubchenco（历史）曲线，对来自美国 NICU（2013-2016 年）的 192,888 名婴儿的体重、长度和头围进行 SGA 或 LGA 分类。
现代曲线将大约 10%的婴儿分类为 SGA，直至 32 周，但年龄较大的婴儿变异增加。INTERGROWTH-21 曲线在 32 周后始终有超过 10%的 LGA 发生率。
虽然 Olsen 和 Fenton 都适合，但 Olsen 曲线总体上最适合我们的美国 NICU 婴儿样本。INTERGROWTH-21 曲线适合 SGA 和 LGA 的年龄较小的定义，但由于样本量有限，超出这些定义的推论是不合理的。INTERGROWTH-21 曲线用于 33 周及以上婴儿的样本在上百分位比我们的美国婴儿样本小。
