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

<p class="MsoNormal"><strong><span>Background</span></strong><span>: Standard pediatric growth curves cannot be used to impute missing height or weight measurements in individual children</span><span>. The Michaelis-Menten equation, <span>used for characterizing substrate-enzyme saturation curves, has been shown to model growth in many organisms including nonhuman vertebrates. </span>We investigated whether this equation <span>could be used</span> to interpolate missing growth data in children in the first three years of life.</span></p> <p class="MsoNormal"><strong><span>Methods</span></strong><span>: We developed a modified Michaelis-Menten equation and compared expected to actual growth, first in a local birth cohort (N=97) then in a large, outpatient, pediatric sample (N=14,695). </span></p> <p class="MsoNormal"><strong><span>Results</span></strong><span>: 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:0.50;90%&lt;1.0]). Growth data were modeled accurately with as few as four values from routine well-baby visits in year 1 and seven values in years 1-3; birth weight or length was essential for best fit. </span></p> <p class="MsoNormal"><strong><span>Conclusions</span></strong><span>: A modified Michaelis-Menten equation accurately describes growth in healthy babies aged 0-36 months, allowing interpolation of missing weight and height values in individual longitudinal measurement series. The growth pattern in healthy babies in resource-rich environments mirrors an enzymatic saturation curve.</span></p>