nurse practitioner vs therapist

nurse practitioner

noun
  • A professional nursing designation recognized in some jurisdictions, denoting an individual who is fully qualified as a nurse and who has additional qualifications and authorization to provide diagnoses and/or treatments, including writing prescriptions . 

therapist

noun
  • Someone who provides therapy, usually professionally. 

  • A psychotherapist specifically. 

How often have the words nurse practitioner and therapist occurred in a corpus of books? (source: Google Ngram Viewer )