Well, you know that medical diagnosis is nothing but one of ideas toward you; doctors do not have any authority to evaluate your psycho or mind; they might be more or less mental.
And remember that labelling and naming do create those outsiders and "patients", who are forced to play those labelled personalities, consciously or unconsciously.
Who indeed does this labelling?
Certainly, Society. Society does, like Matrix, labelling people to keep herself safe.