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Using REDCap

How to use REDCap for collecting clinical data.

Matrix of Fields

If you are using a Likert scale for some of your questions, you can represent that in REDCap as a matrix of fields, which is a little more complicated than a normal field but not too much.


You go to the Online Designer, then select the instrument you want to add this question to. Inside the instrument, find where in the survey instrument you want to add the question and then click on the box "Add Matrix of Fields" (it's right next to the "Add Field" button).


That will open a window to create the matrix. You should put the question in the "Matrix Header Text" field and then add a row for the number of options you are giving the respondent, in the case of your first question that would be 6. Put in the label of the option, like Alerts (best practices advisories), in "Field Label" and then a corresponding variable name (no spaces or special characters), and then click the Required box. Do this for each option.


Then, in the Matrix Column Choices box, list each ranking option on a line. You can use numbers, but it might be good to give them a further guide by spelling it out with Most Frequently, Somewhat Frequently, etc. Make sure you have the same number of choices in this box as there are rows.


Then choose "Single Answer (Radio Buttons)" in "Answer Format" and click the box "Allow only 1 choice to be selected per column (radio buttons only)" under "Ranking". 


Then put a name for the matrix, like frequency_clinical_decision, in the "Matrix group name" field.


Then hit save and you should have a working question that only allows the user to pick one frequency option for each choice.