Is "practitioner" applicable to disciplines other than medical sciences?
Solution 1:
I once gave a talk at an academic conference on public administration. Unlike everyone else there, who were all academics who wrote about public administration but did not do it, I was at the time a 'practitioner' of public administration. When I was thanked for my talk, they said it was good to hear, for once, from a 'practitioner'.
So the word is by no means confined to medicine - and no 'strictly speaking' about it. But the word demands a context: you can't just be a practitioner; you have to have a speciality (or specialty) that you practice.
Solution 2:
One can apparently be a practitioner of change and the composer Maurice Ravel must have been (tongue-in-cheek) a practitioner of the dark arts, according to one author. You can also be a practitioner of educational leadership, a practitioner of crime prevention, or a practitioner of low-carbon education.
CPAs (Certified Public Accountants) can be practitioners too and, in Canada, you can get a permit to be a practitioner of foreign law. You can even take a college course to become a practitioner of feminist activism.
I do think that it is most often seen used for practitioners of various healing arts, but I don't see any reason why you can't talk about data analytics practitioners.
Solution 3:
I've seen it in works of fiction applied to people who practice magic. A person practices law as well, but we don't say they are legal practitioners.