x_to_z: X to Z-score function

In jhchou/peditools: Pediatric Clinical Data Science Tools

X to Z-score function

Description

Function to take vectors of measurements, age, and gender, and unique chart and measure, to return Z score

Usage

x_to_z(x, age, gender, chart, measure = "weight")

Arguments

x	Vector of measurements
age	Vector of age parameters
gender	Vector of genders, either 'm' or 'f'
chart	Uniquely specified chart to obtain LMS parameters for
measure	Uniquely specified measure for the chart. Defaults to 'weight'.

Details

The following charts are available, with their corresponding measures.

chart	age_units	measures
abdel-rahman_2017	months	arm_circ(cm)
addo_2010_skin	years	subscapular(mm), triceps(mm)
cdc_2000_bmi	months	bmi(kg/m2)
cdc_2000_infant	months	head_circ(cm), length(cm), weight(kg)
cdc_2000_pedi	months	height(cm), weight(kg)
fenton_2003	weeks	head_circ(cm), length(cm), weight(kg)
mramba_2017	months	arm_circ(cm)
olsen_2010	weeks	head_circ(cm), length(cm), weight(g)
olsen_2015_bmi	weeks	bmi(g/cm2)
who_2006_infant	months	head_circ(cm), length(cm), weight(kg)
who_2007_skin_arm	months	arm_circ(cm), subscapular(mm), triceps(mm)
zemel_2015_infant	months	head_circ(cm), length(cm), weight(kg)
zemel_2015_pedi	years	bmi(kg/m2), head_circ(cm), height(cm), weight(kg)

Examples

# 3, 10, 50, 90, and 97%ile weight for 8.5 month old female on CDC 2000 infant chart
x_to_z(
    c(6.720327734, 7.197413532, 8.314178377, 9.573546299, 10.2153883),
    rep(8.5, 5),
    rep('f', 5),
    chart = 'cdc_2000_infant',
    measure = 'weight'
  )
round( pnorm( x_to_z(
    c(6.720327734, 7.197413532, 8.314178377, 9.573546299, 10.2153883),
    rep(8.5, 5),
    rep('f', 5),
    chart = 'cdc_2000_infant',
    measure = 'weight'
  ) ), 4)

jhchou/peditools documentation built on Oct. 2, 2023, 7:14 a.m.