Use multiselect listbox without temp tables or SQL updates

SELECT Employees.*
FROM Employees
WHERE IsSelectedVar("frmMultiselectList","lboEmployeeID",[EmployeeID])=-1;

Function IsSelectedVar( _
        strFormName As String, _
        strListBoxName As String, _
        varValue As Variant) _
            As Boolean
    'strFormName is the name of the form
    'strListBoxName is the name of the listbox
    'varValue is the field to check against the listbox
    Dim lbo As ListBox
    Dim item As Variant
    If IsNumeric(varValue) Then
        varValue = Trim(Str(varValue))
    End If
    Set lbo = Forms(strFormName)(strListBoxName)
    If lbo.ItemsSelected.Count = 0 Then
        IsSelectedVar = True 'return all if no items selected
      Else
        For Each item In lbo.ItemsSelected
            If lbo.ItemData(item) = varValue Then
                IsSelectedVar = True
                Exit Function
            End If
        Next
    End If
End Function