Convert a "Yes-No", "True-False" or "Checkboxes (Multiple
Answers)" question in REDCap to a factor holding "No" or
"Yes" or "Unknown". Technically "yes" or "checked" (ignoring case), 1 or
TRUE responses are converted to "Yes". "No" or "unchecked" (ignoring
case), 0 or FALSE are converted to "No". All other values are set to
"Unknown". Also see make_yes_no()
.
make_yes_no_unknown(x)
variable to be converted to hold "No", "Yes", or Unknown"
a factor with "No", "Yes", or Unknown"