The report by Baird et al1 published in this issue of Archives of Disease in Childhood was examined and the following conclusions have been drawn from the evidence presented.

1. The choice of participants in the study appears to have been chosen on the basis of established diagnostic criteria. However, and more importantly, the authors have not examined the aetiology of the children’s autism spectrum disorder (ASD). Furthermore, given that all MMR vaccine manufacturers advise in their fact sheets that in rare cases …