whozr: Calculate z-scores from LMS tables

In simisc/whozr: Convert Raw Anthrops to WHO Z-Scores

Calculate z-scores from LMS tables

Description

Calculate z-scores from LMS tables. Wrappers are provided for use with the WHO growth standards (0-5 years) and WHO growth references (5-19 years): see zwa, zha, zwh, zwl, zba, zhca, zma, ztsa, zssa.

Usage

whozr(y, x, sex, ref, adjust_large_z = FALSE)

Arguments

y	Outcome veariable
x	Predictor, typically age
sex	Sex, coded as "F" and "M"
ref	Reference data. A tibble or data.frame with columns named sex, x,l, m and s
adjust_large_z	Shrink large z-scores towards +/-3? This is done in the WHO's "R macro" but not mentioned in any of the references above. Should only be used for soft-tissue measures (WAZ, BAZ, ACAZ, TCAZ, WHZ, SSAZ), not for hard-tissue measures (HAZ, HCAZ).

Details

Cole, TJ (1990) The LMS method for constructing normalized growth standards. European Journal of Clinical Nutrition 44(1), 45-60.

WHO Multicentre Growth Reference Study Group (2006) WHO Child Growth Standards based on length/height, weight and age. Acta Paediatrica 95(S450), 76-85.

de Onis et al. (2007) Development of a WHO growth reference for school-aged children and adolescents. Bulletin of the World Health Organization 85(9), 660-667.

Value

A vector z of y-for-x z-scores

simisc/whozr documentation built on March 24, 2023, 5:14 p.m.