daz | R Documentation |
The daz()
function calculated the
"Development for Age Z-score".
The DAZ represents a child's D-score after adjusting
for age by an external age-conditional reference.
The zad()
is the inverse of daz()
: Given age and
the Z-score, it finds the raw D-score.
daz(d, x = as.numeric(names(d)), reference = get_reference(), dec = 3) zad(z, x = as.numeric(names(z)), reference = get_reference(), dec = 2)
d |
Vector of D-scores |
x |
Vector of ages (decimal age) |
reference |
A |
dec |
The number of decimals (default |
z |
Vector of standard deviation scores (DAZ) |
The daz()
function return a named vector with
Z-scores with length(d)
elements
The zad()
function returns a vector with D-scores
with length(z)
elements.
Stef van Buuren 2020
Cole TJ, Green PJ (1992). Smoothing reference centile curves: The LMS method and penalized likelihood. Statistics in Medicine, 11(10), 1305-1319.
dscore()
# using gcdg-reference daz(d = c(35, 50), x = c(0.5, 1.0)) # using Dutch reference daz(d = c(35, 50), x = c(0.5, 1.0), reference = get_reference("dutch")) # population median at ages 0.5, 1 and 2 years, gcdg reference zad(z = rep(0, 3), x = c(0.5, 1, 2)) # population median at ages 0.5, 1 and 2 years, dutch reference zad(z = rep(0, 3), x = c(0.5, 1, 2), reference = get_reference("dutch")) # percentiles of D-score reference g <- expand.grid(age = seq(0.1, 2, 0.1), p = c(0.1, 0.5, 0.9)) d <- zad(z = qnorm(g$p), x = g$age) matplot( x = matrix(g$age, ncol = 3), y = matrix(d, ncol = 3), type = "l", lty = 1, col = "blue", xlab = "Age (years)", ylab = "D-score" )
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.