For each column in the passed data frame, the function returns a named list
with the value being the largest/last element after a sort.
For factors, the last level is returned, and for logical vectors TRUE
is returned.
This is used as the default value in ard_dichotomous(value)
if not specified by
the user.
Examples
ADSL[c("AGEGR1", "BMIBLGR1")] |> maximum_variable_value()
#> $AGEGR1
#> [1] ">80"
#>
#> $BMIBLGR1
#> [1] ">=30"
#>