convert yes no data type to 0 1 ms access

Sub modUpsizeTests_CheckBooleansForMissingDefaults()
' Search through all tables with Yes/No fields
' Add any missing defaults

    Dim db As DAO.Database
    Dim tdef As DAO.TableDef
    Dim fld As DAO.Field
    Set db = CurrentDb
    For Each tdef In db.TableDefs
	If Left(tdef.Name, 4) <> "MSys" And _
	    Left(tdef.Name, 4) <> "USys" And _
	    Left(tdef.Name, 4) <> "~TMP" Then
	    For Each fld In tdef.Fields
		If fld.Type = dbBoolean Then
		    If fld.DefaultValue = "" Then
			Debug.Print tdef.Name, fld.Name
			' Set default to false
			fld.DefaultValue = "0"
		    End If
		End If
	    Next
	End If
    Next
End Sub