I used to work as a therapist years ago.
One therapist I knew was very strong in his belief of (over)diagnosis, which I tend to view as (maybe I'm being unkind) inflating problems to book in extra sessions?
Anyway, I got into a right barney with him over him taking one symptom in a child (which is generally content free - so not much more than a bad habit) and conflating this into indicative of some sort of underlying trauma in a child - thus labelling the child without any evidence. He had not yet seen this child but had a session booked with her purely to help her stop this particular habit (think bed wetting/nail biting - not chopping the heads of small creatures).
This was on our professional association website for therapists to discuss any issues or ask for advice.
I am against labelling children, and believe that you do need to work carefully gently with them (and never make assumptions) so that you don't 'push them into they system' - you will find that sometimes parents do worry and over-focus on 'normal' childhood behaviour, that is nothing to be concerned about but if you keep picking at the spot could become A Big Thing.
I basically told him this (and pointed out that her presenting symptoms were generally purely habit based - we studied together so he should have know this anyway) and he got very (male) nasty, aggressive and shouty at me.
It was a long time ago (can't remember if it was me or someone else who complained to our professional society) but got a back-pedalling apology from him.
Had this been now and he had decided that this habit was due to an underlying gender issue god knows how this would have played out. I'd be drummed out of the Bownies I think!