These "definitions" are only in place to assist in the "sorting" process for people to receive special resources. If you have/suffer with ADHD, the label isn't important to you. It's not black and white. When you're constantly failing in school, relationships, finances, and work because conventional models (which work well for a vast majority of people) seem to be incompatible with you.. A person can take a huge hit to their self-esteem. Having the rare ability to fight off those horrible self-worth issues, and internalize their problems to the point that they conclude that it's not their fault, it's just how we're "made" is pretty rare. What I'm trying to say is, it's impossible to accurately "diagnose" ADHD by any formula or algorythem.. as the "true" symptoms of ADHD aren't black and white, they come in a full spectrum of colors.. what's more important is the result of the combined "symptoms", and that's pretty universal... profound impact on academic success, and overall poor quality of life. IMO the "test" for ADHD diagnosis shouldn't be "meeting a certain number of criteria" it should instead be that the patient must meet the universal "end result" I talked about above... shitty quality of life, caused by inability to function in typical structured environments due to any number of prevalent symptoms... AND each of those symptoms should need to be "tested" by applying common therapeutic methods so that the symptom "responds" or improves in a fashion that's typical to others with ADHD. It's very well documented how ADHD impacts people (while this may vary from patient to patient, the end-result is usually caused by very common, well known, symptoms. (ie: Bad grades <- Poor note taking <- Student has many pages in their notebook with 2 things written on them, because they started taking notes (good intention / desire to achieve) but they quickly trail off or get distracted, and by the time they "catch" themselves, they are already missing so much, that they feel "what's the use?" and give up.. usually end up fidgeting in their seat, drumming with pencils, chit chatting, or in my case, it became time to clown around and become a comedian.)

So when these common, documented "end results" present themselves, they should respond to equally well-documented possible resolutions, like having a teacher glance at your notebook as they stroll the room, and if they notice a discrepency, quietly say, "Ralphie, you missed the last one.." and allow the kid to quickly "catch up" by giving them a brief, solid, sentence to write "Industrial Revolution - between 1760 to around 1820 - transition to "new" manufacturing process."

Granted this takes a brief moment away from teaching a class, but it can have a PROFOUND effect for a single student, and IMO, learning needs a little bit of individualized effort.

Bottom line is, we know the result of ADHD.. if they apply, then nail down the individual symptoms likely affecting the result, and apply documented solutions, if the symptom responds typically, then +1, if not -1 (meaning the "symptom" could be caused by something else all-together, either way, it leads to a more accurate diagnosis of ADHD than just applying a number of somewhat vague "criteria" and having a hard cutoff point. The DMS's answer to the problem of having a hard cutoff point is to introduce bullshit "varying levels" of ADHD. If you think about it, saying "they must present at least 3 of the 5 given criteria.. and if they only show 2, but have at least 1 from this other group, and 2 more from this group means they have "kinda sorta ADHD with XYZ modifier" is a bullshit way to say, the system is flawed, so we'll just sub divide the results into 20 different subtypes of the single thing we're trying to diagnose" sorry for the long read, I'm kind of smitten about how the DMS yahoo's cause a ton of mis-diagnosed, and an equal amount of missed-diagnosed ADD cases today.