Data for: A modified Michaelis-Menten equation estimates growth from birth to 3 years in healthy babies in the US

Background: Standard pediatric growth curves cannot be used to impute missing height or weight measurements in individual children. The Michaelis-Menten equation, used for characterizing substrate-enzyme saturation curves, has been shown to model growth in many organisms including nonhuman vertebrates. We investigated whether this equation could be used to interpolate missing growth data in children in the first three years of life and compared this interpolation to several common interpolation methods and pediatric growth models. Methods: We developed a modified Michaelis-Menten equation and compared expected to actual growth, first in a local birth cohort (N=97) and then in a large, outpatient, pediatric sample (N=14,695). Results: The modified Michaelis-Menten equation showed excellent fit for both infant weight (median RMSE: boys: 0.22kg [IQR:0.19; 90%&lt;0.43]; girls: 0.20kg [IQR:0.17; 90%&lt;0.39]) and height (median RMSE: boys: 0.93cm [IQR:0.53; 90%&lt;1.0]; girls: 0.91cm [IQR:0...., Sources of data: Information on infants was ascertained from two sources: the STORK birth cohort and the STARR research registry. (1) Detailed methods for the STORK birth cohort have been described previously. In brief, a multiethnic cohort of mothers and babies was followed from the second trimester of pregnancy to the babies’ third birthday. Healthy women aged 18–42 years with a single-fetus pregnancy were enrolled. Households were visited every four months until the baby’s third birthday (nine baby visits), with the weight of the baby at each visit recorded in pounds. Medical charts were abstracted for birth weight and length. (2) STARR (starr.stanford.edu) contains electronic medical record information from all pediatric and adult patients seen at Stanford Health Care (Stanford, CA). STARR staff provided anonymized information (weight, height and age in days for each visit through age three years; sex; race/ethnicity) for all babies during the period 03/2013–01/2022 followed from bi..., Example R code for fitting weight and/or height data with the MME equation is shown in the MME_growth_fitting.RMD file. This file was written to fit the supplied STARR dataset. However, it can be adapted to alternative data. The HTML version of this file is available as well, in case viewing the script without opening it in R is desired. R_sessionInfo.txt contains the R software version, as well as the versions of the packages included in the code. See the methods section of the manuscript for the description of the starting parameters for the nls() function., # Data for: A modified Michaelis-Menten equation estimates growth from birth to 3 years in healthy babies in the US ## Description of the data and file structure Data for this study include, per baby: sex, age in days, and, over time, weight in Kg and height in cm. Each baby had at least 5 visits. Our goal was to fit each baby’s data to a curve as described by a modified Michaelis-Menten equation, allowing interpolation of missing weight or height values. Among the subset of all infants who had 7 well-baby visits in the first year of life, and 12 visits over 3 years, we further explored the minimum number of, and which, data points were necessary for good fit. Finally, among babies with 5 time points in year 1, and 2 in both year 2 and year 3, we examined whether weight or height data early in life could predict growth in later months. To meet anonymization guidelines, we are providing only STARR data, including sex, age and jittered weight and height (for STORK data, STARR race/e...背景：标准儿科生长曲线无法用于填补个体儿童的缺失身高或体重测量值。米氏方程（Michaelis-Menten equation）原本用于表征底物-酶饱和曲线，现已被证实可对包括非人类脊椎动物在内的多种生物的生长过程进行建模。本研究探讨该方程是否可用于插值填补出生后前三年儿童的生长缺失数据，并将该插值方法与多种常用插值手段及儿科生长模型进行对比。 方法：本研究构建了修正版米氏方程，首先在本地出生队列（N=97）中对比预测生长与实际生长情况，随后又在大型儿科门诊样本（N=14695）中开展相同对比。 结果：修正版米氏方程对婴儿体重与身高均展现出极佳的拟合效果：婴儿体重的中位均方根误差（RMSE, Root Mean Square Error）为，男婴0.22kg[四分位距（IQR, Interquartile Range）：0.19；90%分位数<0.43]，女婴0.20kg[IQR：0.17；90%分位数<0.39]；婴儿身高的中位RMSE为，男婴0.93cm[IQR：0.53；90%分位数<1.0]，女婴0.91cm[IQR：0.... 数据来源：婴儿相关信息来源于两个渠道：STORK出生队列与STARR研究登记库。(1) STORK出生队列的详细研究方法已在既往研究中发表。简言之，该队列纳入了多族裔的母婴群体，随访时间从妊娠中期直至婴儿三岁生日。研究纳入了年龄18~42岁、单胎妊娠的健康女性，每四个月上门随访一次，直至婴儿三岁生日（共9次婴儿随访），每次随访时均以磅为单位记录婴儿体重，并从医疗病历中提取婴儿出生体重与身长数据。(2) STARR（starr.stanford.edu）存储了斯坦福医疗保健中心（加利福尼亚州斯坦福市）收治的所有儿科与成人患者的电子病历信息。STARR工作人员提供了2013年3月至2022年1月期间所有随访至三岁的婴儿的匿名化信息，包括各次随访的体重、身高、年龄（以天计）、性别以及种族/族裔数据，后续内容省略... 示例R代码：利用米氏方程（MME, Michaelis-Menten equation）拟合体重和/或身高数据的示例代码收录于MME_growth_fitting.RMD文件中。该文件原本用于拟合本次研究提供的STARR数据集，但也可适配其他数据集。此外还提供该文件的HTML版本，方便无需在R环境中打开即可查看脚本内容。R_sessionInfo.txt文件记录了本次研究使用的R软件版本以及代码中涉及的所有R包版本。关于nls()函数的初始参数设置，请参阅论文的方法学部分。 研究数据说明：美国健康婴儿出生至三岁的生长情况可通过修正版米氏方程进行估算 数据与文件结构说明：本研究的每名婴儿数据包含以下信息：性别、年龄（以天计），以及随时间变化的体重（单位：千克）与身高（单位：厘米）。每名婴儿至少拥有5次随访数据。本研究的目标是将每名婴儿的生长数据拟合至修正版米氏方程所描述的曲线，以此实现缺失体重或身高值的插值填补。在出生后第一年完成7次婴儿健康随访、三年内共完成12次随访的婴儿亚组中，本研究进一步探讨了获得良好拟合效果所需的最少数据点数量及所需的具体数据点。最后，针对出生后第一年拥有5个时间点数据、第二年与第三年各拥有2个时间点数据的婴儿亚组，本研究分析了婴儿早期的体重或身高数据是否可预测后续数月的生长情况。 为符合匿名化指南要求，本次研究仅提供STARR数据集，包含性别、年龄以及经过扰动处理的体重与身高数据（STORK数据集的相关信息、STARR数据集的种族/族裔字段内容省略...）