An Outpatient's Daughter Has Been Using a Diary to Track

An outpatient's daughter has been using a diary to track the appearance of her mother's decubitus ulcer when the daughter performs the daily dressing change. The patient has been newly consented for participation in the trial of a new product, presumed to accelerate healing and prevent infection. The researcher instructs the daughter in use of the new product and the use of a scale for tracking the ulcer's healing. Scale items are change in total area (width times depth) , drainage color, surrounding tissue integrity, pain, and odor. What are the advantages of using a scale instead of a diary?

A) It reduces all items to a Likert scale.
B) It makes wound care easier.
C) It forces a level of precision that may or may not be present in a diary.
D) It produces numerical data that the researcher can easily analyze in order to provide evidence of difference between the new method and the old method.
E) It makes sure that subjects all will have daily recordings of the variables the researcher intends to measure.