Martha Raye never was a nurse. While she was known to help out in the hospital, she never worked as a nurse, nor was she ever educated as one.
From Marth's official website, I'm pasting this:
hirdly--she was not a nurse. She never got past the 5th grade in school. Although she had nurse's aide (candy striper) training in the 30s she never became a licensed practical or registered nurse. BUT she did learn nursing care via on-the-job (OJT) training during air raids while entertaining troops in Africa and England when an extra pair of hands were much needed for the wounded soldiers. Years later when she spent so much time in Vietnam--her OJT was put to work again. She helped out in the Xray, Triage, Operating Rooms and many other areas. Many soldiers believed she was a nurse in the Army or Army Reserve. She was not though she did hold honorary military titles (ranks).
If you'd like to learn more about this much loved and remarkable woman, click on this link.