The AGD package implements various tools that aid in the analysis of growth data.

Installation

The AGD package can be installed from CRAN as follows:

The latest version is can be installed from GitHub as follows:

install.packages("remotes")
remotes::install_github(repo = "stefvanbuuren/AGD")

Minimal example

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