Use case
This function works the best with ABCD data where the missing codes
are strictly defined. For HBCD data, the missing codes are still
under discussion. The function may work, but for some undecided future
missing codes, the function may not work as expected.
In case of HBCD data or other aribitrary missing codes that one wishes
to convert to NA, it is recommended to use the
sjmisc::set_na_if() function instead.
The data must be type transformed and labelled. See
transf_factor() and transf_label() for details.