What value is passed when an option radio button is selected?

I have a form with two radio buttons, one for Date Received and the other for Date Updated.  This is on an unbound form and the selection determines the filter on an underlying query for another form.  However, when a radio button is slected, what is the value that is passed?  I tried 1, Yes, True, but nothing seems to register.Start Free Trial

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If Me.optDateReceived = 1 Then
  Do Something
End If
 
If Me.optDateUpdated = 2 Then
  Do SOmetihng
End If