Something like this:
Code:
Sub DDOnExit()
ActiveDocument.Unprotect
Select Case ActiveDocument.FormFields("Dropdown1").Result
Case "Positive": Selection.Cells(1).Shading.BackgroundPatternColorIndex = wdBrightGreen
Case "Negative": Selection.Cells(1).Shading.BackgroundPatternColorIndex = wdDarkRed
End Select
ActiveDocument.Protect wdAllowOnlyFormFields, True
End Sub
Set DDOnExit to run "OnExit" from the dropdown. Assumes the dropdown is named "Dropdown1"