A congressional hearing on Tuesday titled “How the Corruption of Science Has Impacted Public Perception and Policies Regarding Vaccines” largely consisted of a debate over an unpublished study comparing chronic illnesses in children who received vaccines with those who didn’t.
The study was lead-authored by Marcus Zervos of Henry Ford Health, completed in 2020, and never submitted for publication, according to testimony during the hearing. Senator Ron Johnson, the chair of the subcommittee for the hearing, and the witness Aaron Siri, a lawyer who has represented RFK Jr and the anti-vaccination non-profit Informed Consent Action Network, both claimed the study was not submitted because the authors would lose their jobs were it to be published.
Zervos and the other authors of the study were not present at the hearing. The study, which has never been peer-reviewed, is not currently available to the public as a pre-print or in any other form.
Henry Ford Health’s communication office did not respond to a request for comment in time for publication.
The only information that is currently publicly available about the study comes from the hearing itself, including witness testimony and a brief trailer for a documentary from the Informed Consent Action Network. The trailer says the study found that “amongst the unvaccinated group, there was zero brain dysfunction, zero diabetes, zero behavioral problems, zero learning disabilities, zero intellectual disabilities, zero tics and zero other psychological disabilities”.
The trailer also includes a clip of Donald Trump saying: “A few decades ago, one in 10,000 children had autism. Today, it’s one in 31.”
Witnesses on both sides of the debate during the hearing agreed that the study in question found no link between vaccines and autism.
Jake Scott, a clinical associate professor of infectious diseases at Stanford – and the only physician who served as a witness during the hearing – had a different explanation as to why the study was not published.
In his testimony, Scott said that the study is “fundamentally flawed”, adding that its core problem was that “vaccinated children had twice the follow up time and substantially more healthcare visits than unvaccinated children”. More healthcare visits mean more opportunities to be diagnosed with conditions like ADHD.
Scott went on to explain that “the study reports zero ADHD cases among 1,000s of unvaccinated children. How is that possible with a national prevalence at 11%? That’s highly unlikely, unless conditions went undiagnosed.” Scott noted that the study also claimed a six to eightfold increase in ear infections among vaccinated children, but there is no plausible scientific explanation as to why vaccines would increase ear infections.
This finding is consistent with past research showing that parents who do not vaccinate their children are also less likely to have their children treated for health conditions in the medical system. Conditions that were not diagnosed or treated would not have shown up in the study, which relied on medical records, according to hearing testimony.
Siri claimed the authors of the study ran sensitivity analyses to account for the differences in medical care. These are not available to the public.
As a point of comparison, Scott referenced a Danish study published this July in Annals of Internal Medicine which investigated whether childhood vaccines were linked to 50 different conditions, including many of the same conditions from the unpublished study, like ADHD, autism, asthma, food allergies and eczema. The Danish study looked at outcomes in over a million vaccinated children and 15,000 unvaccinated children, while the unpublished study looked at 18,500 vaccinated children and 2,000 unvaccinated children, according to hearing testimony.
The Danish study found no statistically significant increase in risk for any of the conditions investigated, and that vaccinated children experienced lower rates of certain conditions, like ulcerative colitis.
Johnson and Siri expressed skepticism over the Danish study, noting that the authors have not released the de-identified raw data they used for their conclusions. No data is available about the unpublished study.
Later in the hearing, the conversation turned towards skepticism about vaccines in general and the Covid-19 vaccine specifically.
Some graphics that Johnson shared left out critical information. For example, a line chart he introduced accurately showed that measles death rates had already begun to decline significantly before vaccines were introduced in the 1960s, due to other factors like improved sanitation, healthcare access and nutrition, but the chart stops in 1960. After vaccines were introduced and widely adopted, both measles cases and death rates declined to nearly zero.
Measles was effectively eliminated in the US in 2000, but cases reemerged when vaccine adoption decreased. There have been 35 measles outbreaks in 2025, according to the CDC. At least two US children and one adult have died of measles this year.
Scott, the Stanford witness, had trouble answering some questions based on spurious facts. He was silent for a moment when Johnson asked him “Did you believe when Fauci told us that the [Covid] mRNA shot would stay in the arm?” There is no credible evidence that Fauci ever said this.
Toby Rogers, a fellow at the Brownstone institute whose study linking vaccines and autism was retracted said: “I believe we are in the midst of one of the greatest crimes in human history,” referring to vaccines. In now-deleted tweets, Rogers has called for hearings similar to the Nuremberg trials for public health officials who promote vaccines.
When Senator Richard Blumenthal, the ranking member of the hearing subcommittee, asked if Rogers believes the Covid-19 vaccine is comparable to the Holocaust, several audience members applauded.