get_reference() R function from [dscore]

Get D-score reference

The get_reference() function selects the D-score reference distribution.


get_reference(
  population = NULL,
  key = NULL,
  references = dscore::builtin_references,
  verbose = FALSE,
  ...
)

Arguments

population: String. The name of the reference population to calculate DAZ. Use unique(builtin_references$population) to obtain the set of currently available reference populations.
key: String. Name of the key that bundles the difficulty estimates pertaining one the same Rasch model. View builtin_keys for an overview of the available keys.
references: A data.frame with the same structure as builtin_references. The default is to use builtin_references.
verbose: Logical. Print settings.
...: Used to test whether the call contained the deprecated argument references.

Returns

A data.frame with the LMS reference values.

Note

No references for population "gsed" exist. The function will silently rewrite population = "gsed"

into to the population = "gsed".

The "dutch" reference was published in Van Buuren (2014) The "gcdg" was calculated from 15 cohorts with direct observations (Weber, 2019). The "phase1" references were calculated from the GSED Phase 1 validation data (GSED-BGD, GSED-PAK, GSED-TZA) cover age range 2w-3.5 years. The age range 3.5-5 yrs is linearly extrapolated and are only indicative. The "preliminary_standards" references were calculated from the GSED Phase 1 validation using a subset of children with healthy development.

Examples


# see key-population combinations of builtin_references
table(builtin_references$key, builtin_references$population)

# get the default reference
reftab <- get_reference()
head(reftab, 2)

# get the default reference for the key "gsed2212"
reftab <- get_reference(key = "gsed2212", verbose = TRUE)

# get dutch reference for default key
reftab <- get_reference(population = "dutch", verbose = TRUE)

# loading a non-existing reference yields zero rows
reftab <- get_reference(population = "france", verbose = TRUE)
nrow(reftab)

References

Van Buuren S (2014). Growth charts of human development. Stat Methods Med Res, 23(4), 346-368.

Weber AM, Rubio-Codina M, Walker SP, van Buuren S, Eekhout I, Grantham-McGregor S, Caridad Araujo M, Chang SM, Fernald LCH, Hamadani JD, Hanlon A, Karam SM, Lozoff B, Ratsifandrihamanana L, Richter L, Black MM (2019). The D-score: a metric for interpreting the early development of infants and toddlers across global settings. BMJ Global Health, BMJ Global Health 4: e001724. https://gh.bmj.com/content/bmjgh/4/6/e001724.full.pdf.

get_reference function