If you’re thinking about writing a thriller featuring an evil scientist, might I suggest selecting Andrew Wakefield as the central antagonist. Few individuals in the history of biomedicine have done as much harm to public health.
From my perspective, there seems little doubt that his deceitful research and twisted advocacy have been a driving force behind the growth of the modern anti-vaccine movement and the rise in outbreaks of infectious diseases, including measles—which kills almost 150,000 people every year, mostly children. Following the advent of this anti-vaccine rhetoric, and no doubt thanks to its legacy, those numbers are rising.
Wakefield’s ascent to the pinnacle of despicableness all started with one small and staggeringly shoddy study. Before his infamy, he was a physician and surgeon, educated in Canada, practising medicine in the UK. In 1998, Wakefield was the lead author on a paper, published in the respected medical journal The Lancet, that claimed there was a connection between vaccination and autism. The research was little more than a case study—which, right out of the gate, needs to be recognized as a highly limited methodological approach. Basically, the paper is not so much a report on a rigorously controlled study as a description of what was observed in twelve children after they received the measles vaccine.
There was no randomization or control group, so the sample of children had the potential to be highly biased. A study of this nature, especially one so small, cannot establish causation. But that didn’t stop Wakefield from suggesting—at a 1998 press conference that one science journalist has called “one of the biggest public relations disasters in medicine”—that his results showed a clear link between vaccines and autism.
No surprise, this sensationalistic spin was picked up and amplified by the popular press. The lie—and it is now clear that it was a blatant and harmful lie—took off. There was a flood of headlines and stories in news outlets like the Daily Mail (“New MMR Link Found to Autism”), New York Times (“The Not-So-Crackpot Autism Theory”), CNN (“I Think There Is a Link”), and 60 Minutes (“Controversial Researcher Claims Link between Vaccine and Autism”) which regularly featured Wakefield and reported on the heart-breaking experiences of parents with autistic children. Celebrity enablers, most notably actress and comedian Jenny McCarthy, amplified Wakefield’s science-free hypothesis.
McCarthy’s infamous appearances on Larry King Live and The Oprah Winfrey Show helped legitimize Wakefield’s message. On Oprah’s show, for example, McCarthy called the measles vaccine “the autism shot,” and the hugely influential host praised her as a “mother warrior.” Many other media outlets gave McCarthy’s message a platform. A piece on ABC News from around the same time opened by highlighting how McCarthy was using her “star power to raise awareness about the dangers of childhood vaccinations that they believe are linked to diseases like autism.” Vaccination rates declined.
Disease outbreaks increased. Children died. For years, there was even a website called the Jenny McCarthy Body Count that tracked the number of vaccine-preventable deaths and illnesses that had occurred since she started her anti-vaccine campaign.
This fear-mongering hype happened despite vigorous pushback by the clinical and biomedical research community almost as soon as the 1998 study appeared, including scientific commentary that the study was methodologically weak, far from conclusive, and counter to the large body of existing evidence that the measles vaccine was safe and highly effective.
While it took far too long, the 1998 paper was finally retracted by The Lancet in 2010. The Wakefield debacle remains a cautionary tale about so many things, including the problem of false balance in the media and how misinformation and fear mongering can be used to build a profitable brand. Wakefield never should have been taken so seriously by the popular press, and his theories should have been positioned as fringe.
Sadly, Wakefield is now a hero in the anti-vaccine community, and he tours the world speaking about this nonsense. But here I want to focus on the enduring role of that one fraudulent 1998 study in The Lancet. It stands as one of the most notorious examples of “zombie science”: how even formally discredited academic papers live on, having ongoing and insidious impact on academic literature, public perception, and health debates.
Wakefield has never replicated his results (no surprise), and there is now a large and well-done body of evidence that tells us, emphatically, that there is absolutely no link between vaccines and autism.
We owe a great debt to investigations of journalists such as Brian Deer, who revealed that not only was Wakefield’s study methodologically questionable but it was also full of falsehoods, data distortions, and conflicts of interest. For example, the research was funded by lawyers acting for parents involved in lawsuits against vaccine manufacturers—which, no surprise, influenced the selection of children for this study.
Indeed, as Deer’s examination revealed, the “undisclosed goal” of the research “was to help sue the vaccine’s manufacturers.” After looking at the details and data surrounding all twelve children in the study, he came to the damning conclusion that “no case was free of misreporting or alteration.” The data for this hugely influential study wasn’t slightly mishandled; it was fraudulent through and through.
Add some research ethics misconduct to the story and it’s no surprise that Wakefield lost his medical licence. In 2010, the General Medical Council, which regulates physicians in the UK, found that he acted “dishonestly and irresponsibly” while doing the research and had “callous disregard” for the child participants.
A retracted, fraudulent, and obviously incorrect study by a completely discredited and unethical author couldn’t still be influential, right? Alas, the zombie data lurches forward. It. Will. Not. Die.
A 2021 study used various metrics to map the power of the 1998 Wakefield paper. The researchers found that it had an almost immediate and negative impact on public perception. Vaccine skepticism increased, as did the almost certainly erroneous reporting of vaccine injuries. There was also a shift in media reporting on vaccines toward the negative—all trends that continued past the retraction. The authors conclude that this demonstrates that “attention to false or misleading vaccine research can impact public confidence in vaccines.”
Yep. Public perception data has consistently found that a depressingly large percentage of the population continued to believe this nonsense. A 2015 survey—five years after the retraction—found that 21 percent of Americans under thirty believed vaccines cause autism, and only 59 percent knew that it is definitely or probably false. Another survey, done the same year in my home province of Alberta, came to the exact same conclusion: 21 percent of the nearly 3,000 interviewed believed vaccines cause autism. It is worth stating again that this tremendously harmful belief, embraced by millions and millions of people around the world, all started with that one, now retracted, study.
I asked Dr. Matthew Motta, the lead author of the above 2021 study and a professor at Boston University’s School of Public Health, about the profound impact of the Wakefield paper. He believes their study “provides strong causal evidence that Wakefield’s piece played an instrumental role in sowing doubt about the safety of childhood vaccines.” This doubt, Motta says, shaped public discourse surrounding the measles vaccine and “the possibility that it might be unsafe.”
Once that doubt was injected, it was difficult to dissipate. The public weren’t the only ones adversely affected by Wakefield’s fraud. A study in 2021 did a thorough examination of how the academic community referenced the 1998 paper. It found, no surprise given the initial hype, that hundreds referenced the fraudulent study as soon as it was released. But paradoxically, post-retraction referencing increased!
From 2011 to 2017, for example, there were 337 academic references to the Wakefield study. Approximately 62 percent failed to explicitly note that it was officially retracted, and only about half of those references were clearly negative in tone. Another analysis, published in 2019, came to a similar conclusion, noting that “a significant number of authors did not document retractions of the article by Wakefield.”
The Wakefield zombie marches on and continues to consume brains, including those of the academic variety.
Why is this happening? “Wakefield’s work is continually reanimated by anti-vaccine activists who feel as if the work is a legitimate contribution to scientific discourse,” Motta tells me. Those pushing a particular agenda keep the study in the public eye. “Anti-vaccine activists are essentially using the language of science—that is, discussing the fact that the piece was published in a prestigious medical journal, lending credence to the study’s methods and findings, etc.—in order to cast doubt on scientific consensus regarding vaccine safety,” Motta says. The study’s retraction by The Lancet fits into the broader anti-vaccine idea that Wakefield was persecuted for bravely speaking the truth. The fake science imparts science-y credibility, while the retraction feeds a fake narrative. Zombies are hard to kill.
Of course, the Wakefield paper isn’t the only retracted study that still lingers and does harm. A 2021 study of over 13,000 papers retracted from 1960 to 2020 came to the depressing conclusion that only 5.4 percent of post-retraction references acknowledged retraction.
Oof. An Economist analysis of 20,000 retracted articles determined that 84 percent received at least one post-retraction citation—which, taken together, amounted to 95,000 post-retraction citations. And those papers were cited in another 1.65 million papers. Like an infectious agent, the zombie not only lives but can also mutate and spread its literature-polluting poison rapidly and far.
As we saw with the Wakefield bunk, some retracted papers thrive in their post-retraction life. A study from the University of Michigan, also published in 2022, did an analysis of almost 4,000 retracted papers to quantify how much attention they received over a ten-year period. The depressing result: retracted papers received more attention—in the popular press, on social media, in academic literature—than studies that are never retracted. This is concerning on many levels; as the authors of the study note, “flawed findings [spread] throughout the scientific community and the lay public.”
There are several reasons for this heightened and continued attention, including the reality that the retraction process itself might generate attention. But I suspect the main reason is that the content of retracted articles is often more exciting than studies that are done rigorously. Bad science can be more extreme, and as a result, it grabs more eyeballs, especially if it plays to a cultural moment and/or feeds a controversial position that demands supportive data. Vaccines cause autism! (Wrong and retracted.) Ivermectin treats COVID-19! (Wrong and retracted.) Police shootings are not associated with anti-Black racism! (Wrong and retracted.)
This last study, originally published in 2019, has been called “fundamentally flawed” by experts in the field and is a good example of how controversy grabs and keeps attention. It has been used by partisan voices to argue against police reform. It even seeped into the language of US president Donald Trump, when, shortly after the murder of George Floyd in the summer of 2020, he made the misleading statement that “more white people” are killed by police—a position almost certainly informed by this study.
This retracted study was viewed as so flawed and misleading that over 850 academics co-signed a letter condemning it as “scientific malpractice.” But as noted in a comment on a study in the Washington Post by professors Dean Knox from the University of Pennsylvania and Jonathan Mummolo from Princeton University, “ideologues now seek to resuscitate this discredited work, claiming the retraction was politically motivated.”
Keeping zombies alive by deploying motivated reasoning—a cognitive bias that leads to the embrace of ideas based on their desirability rather than the evidence—is all too common. Those who liked the outcome of this study, like those who found the Wakefield study helpful to the anti-vaccine agenda, use Olympic-level mental gymnastics to keep it circulating as valid science. They ignore the large body of evidence that runs counter to the conclusions of the retracted study.
And they reason away the retraction, weaving it into a broader storyline that, paradoxically, makes the bogus study appear even more valid and significant. I have personally experienced this twisted thinking when engaging with anti-vaccine advocates or people who believe ivermectin, the now-infamous antiparasitic drug, is a miracle cure.
“Of course, that study was retracted,” they tell me. “Big pharma can’t have those conclusions floating around!” And thus, zombie science claws its way out of the grave, refusing to die.
Excerpted from The Certainty Illusion: What You Don’t Know and Why It Matters by Timothy Caulfield. Copyright © 2025 by Timothy Caulfield. Published by Allen Lane, an imprint of Penguin Canada, a division of Penguin Random House Canada Limited. Reproduced by arrangement with the publisher. All rights reserved.
