Unlike software, it's time-consuming and expensive to test people. Most speculative studies on humans seem to start with a small group, and if they think they f

Unlike software, it's time-consuming and expensive to test people. Most speculative studies on humans seem to start with a small group, and if they think they found something they move up to larger groups. 35 isn't all that terrible, either. An estimated 10 million adults have ADHD (although that sounds bogus to me), and plugging that into a calculator with a 95% confidence, that gives a confidence interval of 16.5. Not sufficient for definitive proof of anything, but still meaningful.