Is there a lock property for a radio list object? I would do this in access forms to control edit access.
'Read Only
object.enabled = false
object.locked = true
'Read/Write
object.enabled=true
object.locked=false

If you do not have code within the radio button list you could lock the control that has code to control the radio list. Like if they selected a choice in the radio list and then clicked a button/link to run the code.

Another idea would be to add code to the radio list that would check their username/role to see if they have rights to edit the options. example

if username = [users name] then
'execute code
else
'display nothing, java script message box saying that can't edit, or redirect to another page, saying you can't edit
end if