I had to take a long questionaire, a computer program testing focus/reactions, and a comprehensive IQ test before I was diagnosed with severe impairment from ADHD a year ago. In fact, I was originally diagnosed with ADHD after taking a comprehension IQ test to get accepted to kindergarten at a magnet school, but my parents figured it was just a phase and never did anything about it.

It's frustrating to think about the lack of consistency in ADHD diagnosises and treatment. In /r/ADHD (ADHD subreddit), some people get diagnosed after a few minutes of talking with a psych. Others live in countries where ADHD isn't even considered a thing. Many went through the same rounds of tests that I did. Even after diagnosis, I had the same problem as several /r/ADHD members in that the first psychiatrist I went to looked at my psychologist's diagnosis and was like "Meh, you got decent grades in high school anyway. You're just stressed/tired/depressed/etc." Wasted my time with four months on four different depression medications before I got a second opinion.