Experts find new study by Geier & Geier on MMR and autism to be seriously flawed

Expert opinion on findings of study by Geier M and Geier D.

Clinical Article. Pediatric MMR Vaccination Safety. Geier M, Geier D. International Pediatrics 2003, 18: 108-13.

Medical and scientific experts find this research seriously flawed, and the conclusions made by the authors to be incorrect for the following reasons:

• The Vaccine Adverse Event Reporting System (VAERS) is not designed to test the hypothesis being investigated.

• VAERS is subject to limitations inherent in any passive surveillance system e.g. stimulated reporting (increased reporting following publicity relating to an alleged adverse reaction).

• The critical issue here is age. This study does not compare 'like with like' as the authors are comparing MMR, which in the USA is given at 15 months with DTwP, which is given at 2, 4, 6 and 15 to 18 months of age in the USA . This failure to compare children of the same age is sufficient to explain the apparent excess of cases reported in the MMR group.

• Since many of the neurological abnormalities examined, such as autism, first become apparent in the second year of life this will automatically lead to a bias in finding a higher incidence of neurological disorders in the MMR group unless they limit the analysis solely to the fourth dose of DTwP.

• The findings of this study contrast dramatically with a number of other studies that have used valid methods for assessing whether there is an increased risk of autism after MMR vaccination. For example, the study by Taylor et al. (Lancet 1999, 353:2026-9) which used a complete database of children with autism in the North East Thames region of London, England and linked this to their immunisation records. This study found no excess of autism with onset within 2 months, 4 months and 6 months of MMR vaccination compared to other time periods. Another example is the study by Madsen et al. (NEJM 2002, 347: 1477-82) which studied the records of over 500,000 children and found no link between MMR and autism.

• The findings of this study are also not consistent with studies done in the UK and the USA showing that trends in the rate of autism bear no relationship with trends in the coverage of MMR.

• The literature review is not comprehensive and does not refer to a number of relevant and important papers.

• Another important issue is the inclusion of reports up to 2000, which includes a three-year period after Wakefield first published his hypothesis. Reports of neurological disorders may therefore, have been made because of this publication, which would not apply to the DTwP vaccine. This would be an important bias in Geier and Geier's findings.

Committee on Safety of Medicines (CSM) advice on methodology used in this paper
Previous research by Geier and Geier, using similar methodology, has been carefully reviewed by the CSM. The advice of the CSM was that this type of analysis (use of spontaneously reported adverse reaction data and numbers of vaccine doses distributed) cannot be used to determine and compare the incidence of adverse reactions associated with different vaccinations.

CSM will shortly be asked to review the current study by Geier and Geier. However, it is clear from CSM's previous advice that this methodology is seriously flawed and the conclusions of the authors concerning the association between MMR and DTP vaccine and the outcomes studied cannot therefore be justified.

Further information

MHRA statement on the Study on safety of MMR vaccine by Geier and Geier.

Here is a link to the American Academy of Pediatrics who have done a good critique of the Geier & Geier paper. http://www.aap.org/profed/thimaut-may03.htm
 

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