I've got to go and finish a book: I'll be back in six months, but in case it kills me, here's what I've learned in eight years of writing this column.

Alternative therapists don't kill many people, but they do make a great teaching tool for the basics of evidence-based medicine, because their efforts to distort science are so extreme. When they pervert the activities of people who should know better – medicines regulators, or universities – it throws sharp relief onto the role of science and evidence in culture. Characters from this community who wonder why people keep writing about them should look at their libel cases and their awesomely bad behaviour under fire. You are a comedy factory. Don't go changing.

This week Baroness Susan Greenfield, professor of pharmacology at Oxford reportedly announced that computer games could cause dementia in children. This would be very concerning scientific information. But this comes from the opening of a new wing of an expensive boarding school, not an academic conference. Then a spokesperson told a gaming site that's not what she means. Though they didn't say what she does mean.

Two months ago the same professor linked internet use with rising autism diagnoses (not for the first time), then pulled back when autism charities and an Oxford professor of psychology raised concerns. Similar claims go back a long way. They seem changeable, but serious.

In an ideal world, you might imagine that scientific papers were only cited by academics on the basis of their content. This might be true. But lots of other stuff can have an influence.

One classic paper from 1991, for example, found that academic papers covered by the New York Times received more subsequent citations. Now, you might reasonably suggest a simple explanation: the journalists of the Times were good at spotting the most important work. But the researchers looking into this were lucky. They noticed the opportunity for a natural experiment when the printers – but not the journalists – of the Times went on strike.