Reference ranges for midupper arm circumference, upper arm muscle area, and upper arm fat area in US children and adolescents aged 1-20 y.

The new reference percentile ranges for midupper arm measures for healthy children provide a useful nutritional assessment tool in a wide variety of settings. Height status (HAZ) has complex independent associations with arm measures irrespective of the distributional ranking by age and sex. Prediction equations that account for these effects further extend the practical use of the new curves.