Sổ tay hướng dẫn được sử dụng để “Chứng minh” Vắc-xin gây ra bệnh tự kỷ

The health secretary, Robert F. Kennedy Jr., says he wants to understand what causes autism. It’s a perfectly laudable goal and one that scientists have been pursuing for decades. But after announcing a large new federal study on the topic, he made a shocking choice by bringing in the vaccine critic David Geier as a researcher.

In the scientific community, Mr. Geier is infamous for the deeply flawed studies he conducted with his father, Mark Geier, claiming that vaccines cause autism. Researchers have long called attention to the serious methodological and ethical defects in their work.

David Geier, left, and his father, Mark Geier, in their home laboratory in 2005.

Marty Katz

The Geiers once created an illegitimate review board for their research, composed of themselves, family members and business associates. They also promoted the drug Lupron, used for chemical castration and prostate cancer, as a supposed treatment for autism, charging $5,000 to $6,000monthly for unproven therapies. As a result, Mark Geier’s medical license was ultimately revoked or suspended by all 12 states in which he was licensed, and David Geier was fined for practicing medicine without a license.

Because of David Geier’s track record and the fact that Mr. Kennedy has said he believes that autism is caused by vaccines, many public health experts think that the upcoming study may echo the same flawed science. We’ve broken down the anti-vaccine research playbook to help you spot the telltale signs of shoddy studies and show why Mr. Geier is such a divisive choice. (Mr. Geier did not respond to The Times’s request for comment.)

To start: Vaccine critics like Mr. Kennedy often give the impression that scientists haven’t seriously researched whether vaccines might cause autism.

In a Times Opinion analysis, we can demonstrate that researchers have.

The conclusion from all of the high-quality studies has been the same for decades: Vaccines do not cause autism.

And yet the misinformation persists, kept alive by flawed research and bad-faith arguments. The victims are the very community that Mr. Kennedy claims to want to help. Resources that could go to high-quality studies are diverted because of this junk science. The Autistic Self Advocacy Network has said that it is “appalled” by the hiring of a “quack” for the government study.

Unfortunately, it can be hard to differentiate good science from bad. Mr. Kennedy has acknowledged how easy it is to manipulate vaccine studies. In a recent interview, he said that “statistics don’t lie, but statisticians do” and that “epidemiological studies are very easy to manipulate.” He went on to describe exactly the kinds of techniques that David Geier has used in his research.

To show how Mr. Geier makes his research look credible, we’re highlighting tactics he has employed on multiple occasions, using a 2017 paper on thimerosal as our example. We picked it because it uses one of the databases that experts suspect will be relied on in the government report, the Vaccine Safety Datalink, to which Mr. Geier has been previously barred from having access.

Source: Centers for Disease Control and Prevention

The Geiers repeated this sort of shoddy science in paper after paper for years. Though the research is flawed, the reason studies like theirs resonate with people is that they offer a simple (though incorrect) answer to why autism diagnoses have increased significantly in recent years. In the United States roughly one in 31 children had an autism diagnosis in 2022, up from one in 150 in 2000.

The best evidence suggests that most of this rise is due to improved awareness, more standardized diagnostic tools, expanded access to screening and changes by the American Psychiatric Association that broadened diagnostic criteria for autism and combined several conditions under the umbrella of autism spectrum disorder.

Essentially, medicine is getting better at identifying autism cases that were always there and more generous in applying the diagnostic label.

A landmark Swedish study illustrates how much of the apparent increase is because of improved detection. Researchers followed twins born from 1993 to 2002, estimating both autism diagnoses and autistic traits in the children. While diagnoses steadily increased, the prevalence of autistic traits remained relatively stable, suggesting that improved diagnostic practices explain much of the rise in autism rates.

There are some biological factors that might have contributed to a genuine rise in autism: People are having children at older ages, and both maternal and paternal age have been associated with a higher risk of autism — though the biological reasons for this still aren’t fully understood.

For mothers, age-related changes in immune system function may play a role; for fathers, the link may be due to genetic mutations that become more common with age. Still, research consistently shows that these factors may explain only a modest fraction of the sudden rise in diagnoses. Data shows most autism risk is determined before birth, through genetic factors and prenatal development.

We absolutely need more research into what drives autism, but if the upcoming government study uses the same kind of manipulation Mr. Geier and others previously employed to show a link between vaccines and autism, we can expect devastating consequences. This will be just the latest in a series of efforts from Mr. Kennedy — from firing vaccine advisersto canceling millions of dollars in vaccine-related research grants to promising an overhaul of the system that handles vaccine injury claims — that threaten the future of vaccines in the United States.

Every dollar spent relitigating the disproven vaccine-autism link is a dollar stolen from research that could actually help people with autism — studies on support services, educational interventions, employment programs and other factors behind autism. This is the cruelest irony: that those who claim to champion people with autism are denying them real research while undermining one of public health’s greatest achievements. Now you know the anti-vaccine playbook — and how not to fall for it.