The fact that the drugs prescribed for it are often abused and passed around in schools. That and the fact that rates of diagnosis have been ridiculously high in some places. I think I read somewhere that 1/3 of boys in Alabama have received a diagnosis of ADHD. At least at one point they were that high, and it was very embarrassing for the profession of psychiatry. So they are very reluctant in many places to give out such diagnoses.
I see. That haven't happened in our country yet. But a lots of children are being screened for hyperactivity and attention problems in schools these days.
My cousin's youngest son of 7yrs was identified as being hyperactive recently.