A case-control study of autism and mumps-measles-rubella vaccination using the general practice research database: design and methodology.
BACKGROUND
An association between mumps-measles-rubella (MMR) vaccination and the onset of symptoms typical of autism has recently been suggested. This has led to considerable concern about the safety of the vaccine.


METHODS
A matched case-control study using data derived form the United Kingdom General Practice Research Database. Children with a possible diagnosis of autism will be identified from their electronic health records. All diagnoses will be validated by a detailed review of hospital letters and by using information derived from a parental questionnaire. Ten controls per case will be selected from the database. Conditional logistic regression will be used to assess the association between MMR vaccination and autism. In addition case series analyses will be undertaken to estimate the relative incidence of onset of autism in defined time intervals after vaccination. The study is funded by the United Kingdom Medical Research Council.


CONCLUSIONS
Electronic health databases offer tremendous opportunities for evaluating the adverse effects of vaccines. However there is much scope for bias and confounding. The rigorous validation of all diagnoses and the collection of additional information by parental questionnaire in this study are essential to minimise the possibility of misleading results.
Smeeth
L
L
Department of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, UK.
Hall
A J
AJ
Fombonne
E
E
Rodrigues
L C
LC
Huang
X
X
Smith
P G
PG
D017668:Age of Onset; D001321:Autistic Disorder / Q000139:chemically induced* / Q000453:epidemiology*; D016022:Case-Control Studies; D015984:Causality; D002648:Child; D002675:Child, Preschool; D003257:Consumer Product Safety; D019992:Databases as Topic; D005194:Family Practice; D006801:Humans; D015994:Incidence; D007223:Infant; D016015:Logistic Models; D022542:Measles-Mumps-Rubella Vaccine / Q000009:adverse effects*; D040442:Public Health Informatics; D011795:Surveys and Questionnaires; D006113:United Kingdom / Q000453:epidemiology
D022542:Measles-Mumps-Rubella Vaccine