getWGS {zscorer}

Calculate z-scores for WHZ, HAZ, WAZ using the WHO Growth Reference (2006) for a single child data.

Description

Calculate z-scores for WHZ, HAZ, WAZ using the WHO Growth Reference (2006) for a single child data.

Usage

getWGS(sexObserved, firstPart, secondPart, index)

Arguments

sexObserved

Sex of child (1 = Male; 2 = Female)

firstPart

Weight (in kg for WHZ and WAZ) or height (in cm for HAZ)

secondPart

Age (in months for HAZ and WAZ) or height (in cm for WHZ)

index

One of "wfh", "hfa", "wfa" (specifies the required index)

Value

z-score of the anthropometric index selected

Warning

The function fails messily when secondPart is outside of the range given in the WGS reference (i.e. 45 to 120 cm for height and 0 to 60 months for age). It is up to you to check the ranges of your data.

Reminders

The reference data for W/H assumes supine length is used for children with a standing height below 85cm

Heights should be specified in cm to the nearest mm (i.e. to 1 d.p.)

Ages should be specified in whole months

Weights should be specified in kg to available precision

The function requires reference data wgsData included in this package

Note

This is a legacy function from the first CRAN release of zscorer which focused mainly on the calculation of z-scores for weight-for-age, weight-for-height and height-for-age. This function has been kept in the package to ensure that existing analysis workflows implemented using the function continue to work.

Examples

  # apply \code{getWGS()} to a make believe 52 month old male child with weight of
  # 14.6 kg and height of 98.0 cm
  waz <- getWGS(sexObserved = 1,     # 1 = Male / 2 = Female
                firstPart = 14.6,    # Weight in kilograms
                secondPart = 52,     # Age in whole months
                index = "wfa")       # Anthropometric index (weight-for-age)
  waz

  haz <- getWGS(sexObserved = 1,
                firstPart = 98,      # Height in centimetres
                secondPart = 52,
                index = "hfa")       # Anthropometric index (height-for-age)
  haz

  whz <- getWGS(sexObserved = 1,
                firstPart = 14.6,
                secondPart = 98,
                index = "wfh")       # Anthropometric index (weight-for-height)
  whz