Dim flag(3) As Boolean
        Dim i As Integer
        For i = 1 To 3
            flag(i) = False
        Next
        i = 0
        Dim control, grpControl As Control
        For Each control In Me.Controls     'find and check group boxes in form's controls
            If TypeOf control Is GroupBox Then  'found a group box
                i += 1
                For Each otherControl In control.Controls 'find and check radio buttons
                    If TypeOf otherControl Is RadioButton Then
                        If otherControl.checked Then
                            flag(i) = True
                        End If
                    End If
                Next
            End If
        Next
        If flag(1) And flag(2) And flag(3) Then
            MessageBox.Show("something checked in each")
        Else
            MessageBox.Show("at least on has nothing checked")
        End If