Meta-analysisindependent cross-checkabstract only checked I-INTB-17 standard review
Vaccines do not cause autism
Vaccines are not associated with autism: an evidence-based meta-analysis of case-control and cohort studies.
Overview
Taylor LE, Swerdfeger AL, Eslick GD. Vaccine 2014 · PMID 24814559 · DOI 10.1016/j.vaccine.2014.04.085
In over 1.2 million children, vaccination was not linked to autism.
Does the study support the specific claim? No · Methodological quality: moderate
Plain-language summary
Study explained simply
- What did the researchers want to find out?
Test vaccine-autism link
- How was the study done?
Meta-analysis
- How many people, animals or samples were studied?
10 studies
- What was actually found?
No association
- How large was the observed effect?
OR 0.99
- What do the results mean in everyday life?
Fear of autism is not a reason to avoid vaccines.
- What are the study's limitations?
Observational; abstract only
- What does it say about Elawady's specific claim?
Contradicts vaccine rejection based on autism fears.
- Do the results apply to Germany and Europe?
High
Scientific in-depth review
1. Full reference
- Authors
- Taylor LE, Swerdfeger AL, Eslick GD
- Journal
- Vaccine
- Year
- 2014
- Identifier
- PMID 24814559 DOI 10.1016/j.vaccine.2014.04.085
- Verification
- verified – PubMed efetch 2026-10-25
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
no COI statement in record
2. Research question
Are childhood vaccinations associated with autism?
3. Study design and population
- Study design
- Meta-analysis – Meta-analysis of cohort and case-control studies
- Population
Children
- Country
Multinational
- Period
search to April 2014
- Sample size
5 cohort studies (1,256,407 children), 5 case-control studies (9,920 children)
- Inclusion and exclusion criteria
Studies on vaccine administration and autism/ASD
4. Methods and endpoints
- Exposure / intervention
Vaccination, MMR, thimerosal, mercury
- Comparator
Unvaccinated/unexposed
- Endpoints
Autism, ASD
- Statistical methods
Pooled OR
5. Actual results
- Results
Cohort data: no relationship between vaccination and autism (OR 0.99, 95% CI 0.92-1.06) or ASD (OR 0.91, 0.68-1.20), MMR (OR 0.84, 0.70-1.01), thimerosal (OR 1.00, 0.77-1.31) or mercury (OR 1.00, 0.93-1.07). Case-control data: no increased risk (OR 0.90, 0.83-0.98; OR 0.85, 0.76-0.95).
- Absolute risks
not applicable
- Authors' conclusion
Vaccinations are not associated with the development of autism or autism spectrum disorder.
6. Strengths
- Over 1.2 million children in cohorts
7. Weaknesses
- Observational data
- Abstract only read
8. Risk of bias
- Orienting tool
- AMSTAR 2
- Type of assessment
- simplified assessment (abstract only)
- Full formal assessment
- no
- Overall risk of bias
- some concerns
- Rationale
Observational primary studies.
9. Assessment of the statistical interpretation
Precise null associations.
10. Relevance to the specific claim
Addresses a common fear behind vaccine refusal.
11. Independent contrary findings
12. Transferability to Germany and Europe
High.
13. Overall methodological judgement
Consistent null finding.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | moderate |
| Risk of bias | some concerns |
| Precision of results | high |
| Directness | direct |
| Reproducibility | replicated |
| Consistency with the overall evidence | consistent |
| Regional transferability | high |
| Adequacy of the interpretation (by the archive) | not applicable |
14. Open questions
15. Linked fact checks
- There are to be no vaccinations: vaccinations, medicines and herbs are forbidden. – Studies contradicting or limiting the claim