I've actually been wondering about this also. I was diagnosed with inattentive ADD as a kid but I wonder if it might have been something else entirely. I mean, I could have been distracted by the cameras that were everywhere then among other things. I found it interesting in my psychological report, the dr. noted that I spaced out so entirely that he had to leave the room and come back later and skip one of the tests. Also, like you said, schizophrenia and adhd have some similar issues that overlap. Knowing what one is what sounds like it could be difficult. In AD/HD executive functioning can be 30% slower to develop than most people, but I'm 24 and have a horrible time with executive functioning still which doesn't make sense according to the one article. Anyways, so I hear what you're saying and I think this is one of the problems in psychiatry is that frequently it's not one clear cut defined thing - they overlap and look like each other often times.