cdcanthro-package: cdcanthro: Sex- and Age-Standardized Metrics from the CDC and...
In cdcanthro: Standardized Metrics Based on the CDC and WHO Growth Charts

cdcanthro-package

R Documentation

cdcanthro: Sex- and Age-Standardized Metrics from the CDC and WHO Growth Charts

Description

Calculation of sex- and age-standardized growth metrics using the LMS method (lambda-mu-sigma). The function cdc_z(), previously named cdcanthro(), uses the 2000 CDC growth charts for children and adolescents with ages of >= 24.0 to < 240 months, to generate sex- and age-standardized z-scores and percentiles for weight, height, and body mass index (BMI). The output includes extended BMI z-scores for values above the 95th percentile to more accurately characterize children with very high BMIs.

Because CDC recommends the WHO Growth Standards for children under 2 years of age, there is also a function, who_z(), which computes sex- and age- (or length-) standardized metrics for children under five years of age.

There is also a function, gradual_z(), which smooths the discontinuities at age 2.0 resulting, in large part, from the use of different reference data. For example, a girl weighing 9.9 kg would be at the 10th percentile the day before her second birthday and at the 2nd percentile the following day.