Well this explains a lot.....
I will be interested to see citations
The BJM retracted the original study as they found out that the guy who authored it had falsified evidence. He was trying to develop some tool for autism and figured he would prove the need. Who knew one person's greed could cause so much harm? (well, until now...) Multiple studies were done, esp in countries with nationalized medicine- they have standardized data banks, etc.- and they were unable to reproduce his results. When they dug deeper and reviewed his evidence~ oh oh.
One of the latest theories is ADD/ADHD/ Autism is an evolutionary development. With multiple devices that allow for or require rapid switching of focus, and the isolation of society (less social interaction face to face) the person with these traits is actually more set up for success. I am not articulating well but it was really interesting. Compound that with the redefinition- Spectrum vs definitive, and increased screening make the numbers captured much higher than 30-40 yrs ago. Then the only people identified were folks who were on the extreme end and many times non-functional.