Do childhood vaccines cause autism?
The weighted evidence overwhelmingly refutes this claim. Large, independent population studies across multiple countries find no association between childhood vaccination and autism; the original study suggesting a link was retracted for fraud.
Claim
Routine childhood vaccination with currently licensed schedules (including MMR) causes autism spectrum disorder at the population level.
Answer
No credible peer-reviewed evidence supports a causal link between childhood vaccination and autism. Nationwide cohort studies following hundreds of thousands of children find no increased risk Hviid 2019, and a meta-analysis spanning more than 1.2 million children reaches the same conclusion Taylor 2014.
The claim originates with a 1998 case series Wakefield 1998 that was retracted after its data were found to be falsified and its author lost his medical license. It is retained here with minimal weight purely to document the origin of the controversy. The persistent public debate is a memetic phenomenon, not a scientific one.
Consensus score
The score is computed deterministically from the citations below, following the methodology in the manuscript (§5). Nothing is hand-tuned per entry — change the evidence and the number moves.
| Citation | sᵢ | mᵢ | tᵢ | e^(−tᵢ/T) | mᵢ·e^(−tᵢ/T) | sᵢ·mᵢ·e^(−tᵢ/T) |
|---|---|---|---|---|---|---|
| Taylor 2014 | −1 | 10.0 | 12y | 0.619 | 6.19 | −6.19 |
| Hviid 2019 | −1 | 9.0 | 7y | 0.756 | 6.80 | −6.80 |
| Madsen 2002 | −1 | 8.0 | 24y | 0.383 | 3.06 | −3.06 |
| DeStefano 2013 | −1 | 6.0 | 13y | 0.595 | 3.57 | −3.57 |
| Wakefield 1998 | +1 | 1.0 | 28y | 0.326 | 0.33 | +0.33 |
| Σ over citations | 34.0 | 19.95 Mₚ | −19.29 Xₚ·Mₚ |
Reading it: the verdict is Strong scientific consensus · No. Direction comes only from Xₚ (tanh is always positive); certainty comes from tanh(Mₚ/W₀) = 0.87. Because Cₚ = 50 when Xₚ = 0 regardless of mass, a balanced stalemate and an unstudied question both read as 50 — which is why Mₚ is always shown alongside the score.
Citations · 5
Vaccines are not associated with autism: an evidence-based meta-analysis of case-control and cohort studies
Increasing exposure to antibody-stimulating proteins and polysaccharides in vaccines is not associated with risk of autism
A population-based study of measles, mumps, and rubella vaccination and autism
Ileal-lymphoid-nodular hyperplasia… and pervasive developmental disorder in children [RETRACTED]
References
Provenance
Score changelog
Generated from citation evidence| Revision | Score Cₚ | Mass Mₚ | Center Xₚ |
|---|---|---|---|
| Current revision | 8 | 19.9 | −0.97 |
| 14 May 2026 | 8↓ 1 | 19.5 | −0.96 |
| 20 Mar 2026 | 9↓ 2 | 18.1 | −0.95 |
| 2 Mar 2026 | 11 | 15.9 | −0.94 |