Always use articles with job roles (in singular form):

• nurse
• doctor
• physiotherapist
• social worker

Nouns which describe the patient in some way also need articles:

Mr James is a single father of 3 small children.

Here are more examples of nouns which describe patients:

• woman
• man
• smoker
• vegetarian
• grandmother

There are two choices of article which could be used with either of these groups:

a/an - when referring to one of many as in the main example in the image

the -  when referring to one specific person [see examples below]:

An appointment with the hospital dietitian has been arranged.

Mr James is the father of Tom, who was admitted yesterday.

 

Read more about articles for medical procedures.

Read more about articles for medical conditions.