redcap

Restrict the selection to one answer of several multiple choice variables

In an instrument I have 4 multiple choice variables (single answer) embedded on a table, and I would like to restrict the answer of these 4 variable to only one. In other words, I would like that only one answer for the 4 variables is possible of being selected.

Currently I can select one from each variable:

enter image description here

But I would like to restricted so only one can be selected among the four: enter image description here

Solution

  • It looks like you're building a dental chart.

    You cannot have multiple fields be mutually exclusive like this. You have to construct this as a single field of type radio in order to allow someone to select only one option.

    I have two suggestions:

    1. Use the Choice Column external module to explicitly tell REDCap to render the 32 choices in 16 columns using the @CHOICE-COLUMNS=16 action tag. This produces the following. enter image description here

    2. Use the Image Map external module and use the TEETH image map as illustrated in the module's GitHub README.

    enter image description here

    However, it uses the Universal dental numbering system rather than the ISO system, and it appears to allow multiple teeth to be selected, even though only the last selection made is recorded. So this may not meet your needs.

    There is also another module that allows you to create a custom imagemap, creatively called Custom Imagemap.