Mixed Effects Analysis of Height Growth in Ethiopian Children Aged 1-12 Years: A Cohort Study

Modelling physical growth is a key component to examine and identify definingcharacteristics in the growth process.The goal of this study was to model and captureknown features of height growth in Ethiopian children aged 1–12 years. Heightmeasurements of 1760 children followed from 1 to 12 years at Young Lives Ethiopia, ayounger cohort,used in the study. The mixed effects method was used to estimate the rateof change within and between subjects over time and to identify defining covariates.Adultheight and rate of change over time were individual-specific resulting individual-levelgrowth differences. There was a negative relationship between individual-specific adultheight and rate of change over time. The decelerated rate of change was observed fromchildhood to the onset of puberty in both sexes. Boys were taller than girls between theages of 3 and 7 years. Mother’s educational status, access to quality drinking water, age,and sex had a significant effect on height growth. Children who had a decelerated rate ofgrowth change during the childhood period become taller later in life. Adult height couldbe determined by an individual-specific rate of change over time.