Ten years ago, a clinical research paper triggered widespread and persistent fears that a combined vaccine that prevents measles, mumps and rubella — the so-called MMR vaccine — causes autism in young children. That theory has been soundly refuted by a variety of other research over the years, and now a new study that tried to replicate the original study has provided further evidence that it was a false alarm. The initial paper, published in The Lancet, the prestigious British medical journal, drew an inferential link between the vaccine, the gastrointestinal problems found in many autistic children and autism. In...