Run Macro When Form Control Checkbox Changes

I have many Form Control Check Boxes that all link to another sheet on row 3.

I have many changes to make but only want to implement the change related to the check box.

This code works perfect when you manualy type true or false on row 3 but not if the check box makes the change.

Private Sub Worksheet_Change(ByVal Target As Range)
ThisCol = Target.Column
If Target.Row = 3 Then
RESULT = MsgBox(Cells(1, ThisCol) & " = " & Cells(3, ThisCol), vbOKOnly, "CLICK RESULTS")
End If
End Sub

Why does this not work when a check box changes the value in row 3?