I'm building an application for my office that allows users to search a database of resources. I've been asked to design a "Wizard" style interface to avoid a long, cumbersome form. It basically works like this:

Step 1)
You pick your role (i.e. what do I do for a living). This is a set of radio buttons.

Step 2)
You choose the catagory(ies) that you're interested in. This is a set of checkboxes.

Step 3)
You pick the subcatagory(ies) you're interested in. This is a set of checkboxes.

Step 4)
You choose your level of proficiency. This is a set of radio buttons.


It works well, BUT, there are situations where you can arrive at the dreaded "no records returned" result. What I'd like to do is for each step, eliminate the choices in the next step that don't have any records. Aside from querying each of the possibilities (and in step 3 there are around 30), I can't think of a good way to do this.

Any ideas?