The Lancet has finally, finally withdrawn a long-discredited study linking autism to vaccinations for measles, mumps, and rubella. The ethical problems behind the research have long been noted, and other studies have failed to repeat the findings. But the retraction comes too late to stop the 1998 study from doing damage. Money is diverted to studying vaccines rather than finding the real causes of and solutions to autism, and parents are refusing to get their children vaccinated. That's led to an increase in diseases we know definitely hurt children, like measles, in developed countries that had long seen them disappear. It's also helped perpetuate the idea that people like Jenny McCarthy know what they're talking about and that personal perceptions are good substitutes for research and evidence. Unfortunately, a retraction isn't going to change the minds of the true believers. -- Monica Potts