Standardizing Anthropometric Measures in Children and Adolescents with Functions for Egen: Update

Abstract

In this article, we describe an extension to the egen functions zanthro() and zbmicat() (Vidmar et al., 2004, Stata Journal 4: 50–55). All functionality of the original version remains unchanged. In the 2004 version of zanthro(), z scores could be generated using the 2000 U.S. Centers for Disease Control and Prevention Growth Reference and the British 1990 Growth Reference. More recent growth references are now available. For measurement-for-age charts, age can now be adjusted for gestational age. The zbmicat() function previously categorized children according to body mass index (weight/height2) as normal weight, overweight, or obese. “Normal weight” is now split into normal weight and three grades of thinness. Finally, this updated version uses cubic rather than linear interpolation to calculate the values of L, M, and S for the child's decimal age between successive ages (or length/height for weight-for-length/height charts).