Preece-Baines Model 1 to Estimate Height and Knee Height Growth in Boys and Girls From Merida, Mexico.

BACKGROUND: Height and body segments in children have differential pubertal growth characteristics. Lower leg length is a sensitive indicator of child's nutritional status. OBJECTIVE: The purpose of this study was to estimate differential timing and tempo of height and knee height (KH) growth in 9- to 17-year-old boys (n = 475) and girls (n = 500) from Merida, Mexico. METHODS: In this cross-sectional study, the Preece-Baines growth curves-model 1 (PB 1) was fitted to the anthropometric data for height and KH. RESULTS: Based on the PB 1 model, KH had earlier age at maximum increment than height in boys (height = 12.37 years, KH = 11.54 years) and girls (height = 11.01 years, KH = 10.93 years). Peak velocity of these 2 dimensions was different in both sexes (boys: height = 7.11 cm/yr, KH = 2.25 cm/yr; girls: height = 5.14 cm/yr, KH = 1.45 cm/yr). Differences ( P <.001) by sex were also observed for the estimated size at peak velocity and final size of height and KH. CONCLUSIONS: When compared to height, KH was shown to have earlier adolescent growth spurt and a smaller difference between final size and the size at maximum (peak) velocity indicating an earlier age for achieving adult size. Overall, the studied boys and girls had short estimated final size, an earlier age at maximum increment, and a lower peak velocity in height than urban Guatemalan peers, the only regional reference available.