WHO DECIDES WHICH FACTS ARE TRUE? In 1998 Andrew Wakefield, a British gastroenterologist with a history of self-promotion, published a paper with a shocking allegation: the measles-mumps-rubella vaccine might cause autism. The media seized hold of the story and, in the process, helped to launch one of the most devastating health scares ever. In the years to come Wakefield would be revealed as a profiteer in league with class-action lawyers, and he...