Any radio button created belongs to the actual form it was created on.
As long as the form is in the uses clause on other forms, then you can access its components and states.
If you have a form named SETUP and a form named CODE,
Then:
CODE.RadioButton1 will access properties on this radiobutton from Setup section/form.
OR, From CODE form:
SETUP.RadioButton5 will access this SETUP RadioButton.
I hope this is understandable :-)
Best regards.