In this week's National Post column I analyze the implications of new Canadian data on Ritalin prescriptions and divorce. (You can read the original study here.) If you're a child, negative life events at home seem to have a lot to do with whether you get diagnosed with attention deficit-hyperactivity disorder. Which would seem to be a bit of a blow to those who insist that ADHD is a neurological illness which has nothing at all to do with parenting—indeed, it would seem to make that view nearly insupportable—and an important point in favour of those who have argued that the explosion of ADHD diagnoses is part of a trend toward medical modification of personality traits. Send angry e-mails to the usual address, not that you need to be told.