MMR & autism: summary of case studies Feb 2001
- Vaccine Affect
- Jun 9
- 2 min read
Smeeth, Hall et al
A case-control study of autism and mumps-measles-rubella vaccination using the general practice research database: design and methodology
BMC Public Health 1, 2 (2001)
Published: 15 February 2001
In this study protocol researchers plan to identify via data derived from the United Kingdom General Practice Research Database children with a possible diagnosis of autism. “MMR vaccination and pervasive developmental disorders: a case-control study” was later published in November 2004.
Here is a summary of studies mentioned in this protocol that have looked at this MMR vaccine and autism:
In a small study from Finland, among 31 children who had reported a gastrointestinal adverse reaction to MMR vaccination, none had subsequently developed signs of autism.
A similar larger study looked at all notified serious adverse events following MMR vaccination in Finland over a 14 year period. There were no new cases of autism among 173 notified adverse events.
However such routine passive surveillance systems have a number of weaknesses for epidemiological studies. There is no control group, the quality of the data may be suboptimal and detecting an effect depends entirely on clinicians believing a new illness was due to vaccination.
In Sweden no increase was apparent in the incidence of autism following the introduction of MMR vaccination
Both these studies included small numbers of children with autism and had limited ability to assess the link between MMR vaccine and autism.
The United Kingdom Committee on Safety of Medicines set up a working party to assess parental and medical reports of children who had developed autism, Crohn's disease or similar disorders following MMR vaccination.
The Working Party Report could not prove or refute the suggested associations between MMR vaccine and autism.
A single large high quality epidemiological study included 293 children with confirmed autism from North Thames health districts. The authors concluded there was no evidence to support an association.
