I'm not sure what you have in mind here and in some possible interpretations of what you want, whether or not you are using FIleMaker 13 will make a big difference here.
A conditional value list can be set up such that the value you choose in field 1's value list controls what list of values appear in the value list for field 2.
A variety of methods can also be used to control whether field 2 even appears on your layout or not depending on the value selected in Field 1. (In FileMaker 13, there's a new feature, Hide Object When, that makes this very simple to set up.)
Which did you have in mind here?
Thanks, Phil. Sorry, I made a mistake in my description. Actually, what I'm trying to do is:
Create something like this:
Do you have an illness? (if the answer is yes, then other fields such as Asthma (Yes or No) or Diabetes (Yes or No) would appear?
And what version of FileMaker are you using?
One very simple way to do this is to set up a tab control. You could put your questions: "Asthma (Yes or No) or Diabetes (Yes or No), etc" on an "Have Illness" tab of the tab control.
But there a number of other options that could also work.