# How can I display a question with compound answers?

I've got to display to the user options to set a value into one of four states:

• A1
• A2
• B1
• B2

Is it better to have a radio button enumerated as above or two sub questions:

• A or B?
• 1 or 2?

and then combine them behind the scenes?

These options could be phrased to allow either two pairs of radio buttons or two checkboxes so I'm not really interested in that aspect. The question is whether we have a single question with four choices or two questions each with two choices.

It has been decided, by someone else, that this is to be stored as a single value and so I can't easily change this without having a serious knock on effect in the system.

• You should still be able to discern separate choices from one value, if you use multiple characters. For example if you have an A/B and an 1/2 choice, you can save as binary 00, 01, 10, 11. If you want to include 'both' as a possible selection, you can have 0 for none, 1 for A, 2 for B, 3 for AB, or you can have a 4-character binary notation (A2 = 1001). It's a bit of a hack, but can work. Commented Aug 15, 2017 at 10:56

I would only recommend breaking 1 question with 4 options into 2 questions with 2 options each in two situations:

First, if there was a linear relationship between the options (for example, if picking A over B changes the value of 1 and 2).

Second, if picking between A and B is so difficult that it must be a separate decision in the workflow from the 1 or 2 decision (or vice versa).

If the premise in Joel's answer applies -- namely that you really have one question with four separate answers -- then you should probably keep it as one question (unless his exceptions apply).

If, however, you really do have two essentially orthogonal (unrelated) questions, then you should -- for the most part -- ask them as two separate questions. (E.g. "Coffee or tea" and "Large or regular").

In limited cases (e.g. lack of space) you could combine them (e.g. have a "Select Drink" drop-down that lists "Large tea", "Regular tea", "Large coffee" and "Regular coffee"), but this should probably only be done as a last resort (if you later added "with or without sugar", the list would start to become cumbersome).

Note: how you actually store the overall response should have no bearing on how you ask the question(s).

• I did debate whether to add the point about how the response is stored. but in the end decided to include it. Commented Aug 15, 2017 at 10:24