Calculate birth weight SDS relative to Dutch references

Calculate birth weight SDS relative to Dutch references

Usage

calculate_birth_z(y, sex, ga, yname = "wgt", dec = 3)

Arguments

y

Birth weight (grammes) or birth length (cm). May be a vector. Converted to numeric.

sex

Character, either "M" (male) or "F" (female)

ga

Gestational age, completed week (Integer or character)

yname

Either "wgt" (for birth weight) or "hgt" (for birth length)

dec

Number of decimals for rounding

Value

 Numeric vector of `length(bw)` elements with
         standard deviation scores relative to Dutch birth
         weight references

Author

 Stef van Buuren, 2019

Examples

calculate_birth_z(c(2500, 3000), sex = "M", ga = 36)
#> [1] NA NA