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Determine if a given observation in the data set is wasted or not, and its respective form of wasting (global, severe or moderate) on the basis of z-scores of weight-for-height (WFHZ), muac-for-age (MFAZ), raw MUAC values and combined case-definition.

Usage

define_wasting(
  df,
  zscores = NULL,
  muac = NULL,
  edema = NULL,
  .by = c("zscores", "muac", "combined")
)

Arguments

df

A tibble object. It must have been wrangled using this package's wrangling functions for WFHZ or MUAC, or both (for combined) as appropriate.

zscores

A vector of class double of WFHZ or MFAZ values.

muac

An integer or character vector of raw MUAC values in millimeters.

edema

A character vector indicating edema status. Default is NULL. Code values should be "y" for presence and "n" for absence of nutritional edema.

.by

A choice of the criterion by which a case is to be defined. Choose "zscores" for WFHZ or MFAZ, "muac" for raw MUAC and "combined" for combined. Default value is "zscores".

Value

The tibble object df with additional columns named named gam, sam and mam, each of class numeric containing coded values of either 1 (case) and 0 (not a case). If .by = "combined", additional columns are named cgam, csam and cmam.

Examples

## Case-definition by z-scores ----
z <- anthro.02 |>
  define_wasting(
    zscores = wfhz,
    muac = NULL,
    edema = edema,
    .by = "zscores"
  )
head(z)
#> # A tibble: 6 × 17
#>   province strata cluster   sex   age weight height edema  muac wtfactor   wfhz
#>   <chr>    <chr>    <int> <dbl> <dbl>  <dbl>  <dbl> <chr> <dbl>    <dbl>  <dbl>
#> 1 Zambezia Rural      391     1  6.01    8.2   68   n       152     825.  0.349
#> 2 Zambezia Rural      404     2  6.01    7.1   65.1 n       139     287. -0.006
#> 3 Zambezia Rural      399     1  6.11    7.6   64.1 n       155     130.  0.9  
#> 4 Zambezia Urban      430     2  6.14    7.9   65.9 n       148    1277.  0.876
#> 5 Zambezia Urban      468     2  6.28    6.6   59.7 n       132     792.  1.38 
#> 6 Zambezia Urban      517     2  6.34    6     61.8 n       129     480. -0.583
#> # ℹ 6 more variables: flag_wfhz <dbl>, mfaz <dbl>, flag_mfaz <dbl>, gam <dbl>,
#> #   sam <dbl>, mam <dbl>

## Case-definition by MUAC ----
m <- anthro.02 |>
  define_wasting(
    zscores = NULL,
    muac = muac,
    edema = edema,
    .by = "muac"
  )
head(m)
#> # A tibble: 6 × 17
#>   province strata cluster   sex   age weight height edema  muac wtfactor   wfhz
#>   <chr>    <chr>    <int> <dbl> <dbl>  <dbl>  <dbl> <chr> <dbl>    <dbl>  <dbl>
#> 1 Zambezia Rural      391     1  6.01    8.2   68   n       152     825.  0.349
#> 2 Zambezia Rural      404     2  6.01    7.1   65.1 n       139     287. -0.006
#> 3 Zambezia Rural      399     1  6.11    7.6   64.1 n       155     130.  0.9  
#> 4 Zambezia Urban      430     2  6.14    7.9   65.9 n       148    1277.  0.876
#> 5 Zambezia Urban      468     2  6.28    6.6   59.7 n       132     792.  1.38 
#> 6 Zambezia Urban      517     2  6.34    6     61.8 n       129     480. -0.583
#> # ℹ 6 more variables: flag_wfhz <dbl>, mfaz <dbl>, flag_mfaz <dbl>, gam <dbl>,
#> #   sam <dbl>, mam <dbl>

## Case-definition by combined ----
c <- anthro.02 |>
  define_wasting(
    zscores = wfhz,
    muac = muac,
    edema = edema,
    .by = "combined"
  )
head(c)
#> # A tibble: 6 × 17
#>   province strata cluster   sex   age weight height edema  muac wtfactor   wfhz
#>   <chr>    <chr>    <int> <dbl> <dbl>  <dbl>  <dbl> <chr> <dbl>    <dbl>  <dbl>
#> 1 Zambezia Rural      391     1  6.01    8.2   68   n       152     825.  0.349
#> 2 Zambezia Rural      404     2  6.01    7.1   65.1 n       139     287. -0.006
#> 3 Zambezia Rural      399     1  6.11    7.6   64.1 n       155     130.  0.9  
#> 4 Zambezia Urban      430     2  6.14    7.9   65.9 n       148    1277.  0.876
#> 5 Zambezia Urban      468     2  6.28    6.6   59.7 n       132     792.  1.38 
#> 6 Zambezia Urban      517     2  6.34    6     61.8 n       129     480. -0.583
#> # ℹ 6 more variables: flag_wfhz <dbl>, mfaz <dbl>, flag_mfaz <dbl>, cgam <dbl>,
#> #   csam <dbl>, cmam <dbl>