Opinion | The Playbook Used to ‘Prove’ Vaccines Cause Autism

[–>The first red flag is in the title: The authors looked only at children with atypical autism, a former diagnosis for people who didn’t meet standard autism criteria.

In proper scientific research, the authors would provide a reason that vaccines might affect this form of autism and not autism more broadly. The authors provide no such rationale. Without one, this looks like what researchers call fishing or p-hacking — the testing of multiple outcomes until you find one that shows a link by chance.<!–>

–> A zoom in on the first page of the study, with the phrase “atypical autism diagnosis” highlighted.<!–>

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[–><!–>The next problem is much more egregious. In a study like this, you should have two groups: people with the condition (cases) and similar people without it (controls) from the same period, so that researchers can spot what’s different between them. But here, the authors define their cases as children with atypical autism born from 1991 to 1998, while the control group includes kids born only in 1991 and 1992.–><!–>

–> The second page of the study, zooming in on the section describing how the cases and controls were chosen. For the cases, the phrase “born from 1991 to 1998” is highlighted, and for the controls, the phrase “born from 1991 to 1992” is highlighted.<!–>

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[–>This is deceptive, given what changed during this period.

The hepatitis B vaccine was added to the list of recommended childhood vaccines in 1991, and significantly broader new autism diagnostic criteria were published in 1994, meaning more people could be diagnosed with atypical autism. Comparing children from before and after those changes can create the illusion of a connection.<!–>

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A line chart showing the hepatitis B vaccination rate for children 19 to 35 months old from 1991 to 1998. Hepatitis B was added to the childhood vaccine schedule in 1991, so there’s no rate shown for that year. In 1992 the rate was a little under 10 percent and rose to above 80 percent by 1996. In 1994 the autism diagnostic criteria were broadened.<!–>

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[–><!–>Mr. Geier acknowledged another major problem with the study: They didn’t take into account confounders — outside factors that can create the appearance of a connection between two things. For example, health care access: Children who see doctors regularly are more likely both to get vaccines and to have developmental concerns noticed and diagnosed. You have to account for that.–><!–>

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Another page of the study, zooming in on the discussion section. Part of a sentence is highlighted: “Among the potential limitations of the present study, it was possible that unknown biases or confounders could be present.”<!–>

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[–>The researchers dismiss the need to include confounders, claiming that other studies using the same data set found that they had no effect.

But many known confounders for vaccines and autism should have been taken into account, including health care access, socioeconomic status, parental age, family history of autism, birth weight and environmental exposures. Without controlling for any of these factors, the study can’t actually tell us anything.<!–>

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The same paragraph, this time with the phrase “This seems unlikely” highlighted.<!–>

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[–>Even worse, all of the studies they cite as justification for ignoring confounders are their own. This is a pattern for the Geiers.

While some personal citing is normal, relying solely on your own work to prove your argument suggests that there’s not much evidence in your corner.<!–>

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The citations section of the paper, with 11 of the 43 citations highlighted, indicating that they were published by the Geiers. Four of their citations are circled, to show that they were the studies that the Geiers used to justify ignoring potential confounding factors.<!–>

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[–>And though the overall list of references might look scholarly, it’s riddled with problems.

Mr. Geier cites this study, for instance, as suggesting that mercury is a known cause of autism and that thimerosal is a significant source of mercury exposure in children. But that study looked at a different, highly toxic form of mercury found in fish, not the type contained in thimerosal.<!–>

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A zoom in on the second citation, a paper titled “Neurobehavioral Effects of Developmental Toxicity.”<!–>

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[–><!–>Mr. Geier also discredits multiple high-quality studies that found no association between thimerosal and autism by arguing that several critical reviews have found methodological flaws in those studies.–><!–>

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A zoom in, with five of the citations highlighted, none of them by the Geiers. All are high-quality studies that found no link between thimerosal and autism and that the Geiers discredited.<!–>

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[–><!–>Those critical reviews? They were published by the Geiers. The second study highlighted here, focused on supposed conflicts of interest in autism research, was initially retracted for having too many errors and — ironically enough — for failing to disclose the authors’ conflicts of interest.–><!–>

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A zoom in, with the next two citations highlighted, both by the Geiers, which they used to discredit the high-quality studies.<!–>

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