I've given an answer on this question: Determine whether all radio button groups have one checked box
It was closed before, but I've rephrased the question better and voted to reopen it.
However, in the meantime the OP claims that they want to accept my answer but is unable to do so. Verbatim comment:
Yes I want to accept this answer. It seems the tick-box you mentioned just isn't there. Perhaps because this question has been closed?
I would say that's not possible; is it?