ClaimsNate Silver

“It sure seems very likely that people who got one dose of J&J would benefit from getting a booster of Pfizer or Moderna.”

Nate Silver, writing on X 29 June 2021 Post by @NateSilver538 on X, 2021-06-29 (X)

Prediction Biosecurity

It seems very likely that people who received one dose of the J&J COVID vaccine would benefit from a Pfizer or Moderna booster.

Mostly true True in substance, wrong in a detail.

Prediction: Statements about events outside the person's control, checked once they fell due: did they come true?

The second judge would not resolve this claim; the verdict shown is the first judge's.

What would count as true or false

A hedged ('very likely') prediction, judged against clinical and regulatory evidence available by mid-2022. True: studies (e.g. NIH mix-and-match trials or real-world effectiveness data) show that J&J single-dose recipients who got a Pfizer or Moderna booster had meaningfully higher immune responses or protection than those with no booster, and regulators (FDA/CDC) authorized or recommended mRNA boosters for J&J recipients. Mostly true: a clear benefit is shown, but on narrower measures only (e.g. antibody levels without clinical outcome data). Mixed: evidence of benefit is inconsistent or limited to some subgroups. Mostly false: mRNA boosters gave little benefit over a J&J booster or no booster for most recipients. False: evidence shows no benefit, or net harm, from an mRNA booster for J&J recipients.

Set before the research began.

Evidence (3)

  1. E1 Effectiveness of Homologous and Heterologous COVID-19 Booster Doses Following 1 Ad.26.COV2.S (Janssen [Johnson & Johnson]) Vaccine Dose Against COVID-19–Associated Emergency Department and Urgent Care Encounters and Hospitalizations Among Adults — VISION Network, 10 States, December 2021–March 2022 CDC, Morbidity and Mortality Weekly Report (MMWR) · 1 April 2022

    “VE against COVID-19–associated emergency department/ urgent care visits was 24% after 1 Jansen dose, 54% after 2 Jansen doses, and 79% after 1 Janssen/1 mRNA dose, compared to 83% after 3 mRNA doses.”

  2. E2 Immunogenicity and Reactogenicity of Vaccine Boosters after Ad26.COV2.S Priming Erasmus University Rotterdam research portal (pure.eur.nl); published in NEJM · 10 March 2022

    “Boosting with any available vaccine was better than not boosting.”

  3. E3 Mix-and-match trial finds additional dose of COVID-19 vaccine safe, immunogenic National Institutes of Health (NIAID media advisory) · 26 January 2022

    “For each primary EUA COVID-19 vaccine, heterologous boosts elicited similar or higher antibody responses as compared to responses to a homologous booster.”

Reasoning

A CDC study from the VISION Network (E1) estimated vaccine effectiveness against emergency department and urgent care visits from December 2021 to March 2022. It was 79% after one Janssen dose plus an mRNA booster, against 24% after a single Janssen dose. An NEJM study (E2) found that boosting J&J-primed people with any available vaccine was better than not boosting. The NIH mix-and-match trial (E4) found that mixed-vaccine boosters produced similar or higher antibody responses than same-vaccine boosters. Together these show a clear benefit, including on clinical outcomes. However, none of the evidence shows that the FDA or CDC authorized or recommended mRNA boosters for J&J recipients, which the criteria require for a fully true verdict.

Cite this claim

Nate Silver, “It seems very likely that people who received one dose of the J&J COVID vaccine would benefit from a Pfizer or Moderna booster.” (said 29 June 2021). Verdict: mostly true. Reliability API, claim c_dc12ab492306, method 0.1.0+28da144b, dataset release v1.1.2. https://epistacklabs.com/claims/c_dc12ab492306

This claim is in dataset release v1.1.2, with the same verdict.

Reply to this claim

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  5. Mixed Prediction 8 September 2023
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All of them

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