Tools for the analysis of growth data: to extract an LMS table from a gamlss object, to calculate the standard deviation scores and its inverse, and to superpose two wormplots from different models. The package contains a some varieties of reference tables, especially for The Netherlands.
The AGD package implements
various tools that aid in the analysis of growth data.
The AGD package can be installed from CRAN as follows:
install.packages("AGD")
The latest version is can be installed from GitHub as follows:
install.packages("remotes")
remotes::install_github(repo = "stefvanbuuren/AGD")
library(AGD)
# What is the SDS of a height of 115 cm at age 5 years
# relative to Dutch references?
# Calculate for boys and girls:
y2z(y = c(115, 115), x = 5, sex = c("M", "F"))
#> [1] 0.424 0.706
# What are the SDS of the IOTF BMI cut-off values for
# overweight (boys 2-18) relative to Dutch references?
cutoff <- c(
18.41, 17.89, 17.55, 17.42, 17.55, 17.92, 18.44, 19.10,
19.84, 20.55, 21.22, 21.91, 22.62, 23.29, 23.90, 24.46,
25.00)
age <- 2:18
z <- y2z(y = cutoff, x = 2:18, sex = "M", ref = nl4.bmi)
plot(age, z, type = "b", xlab = "Age (years",
ylab = "SDS IOTF (on Dutch reference)")
Standard deviation score of IOTF
overweight cut-off relative to Dutch reference