In some cases it's really clear, in some others it isn't. A few of my friends did better than me in school, and they had access to Ritalin. They were pretty good student while I was a problem child. I never really explored the option during school as I didn't really know how it worked and what ADHD was. I tried it later in life and it helped with work. Ritalin probably would have helped me during school. But was it because of some "real" ADHD? Was it because it's a stimulant and it helps anyone? Was my ADHD more or less real than them? I know that for them Rilatin and ADHD was a part of their identity, so maybe they convinced themselves they couldn't work without it? I don't think there's any good and objective way to measure that. Should I feel guilt when I take Ritalin now? I can function without it, but they can too. It's just far from optimal.