A study based on anonymous email surveys of mothers who homeschool their children that suggested a correlation between vaccines and autism was published online on November 21st, 2016 in the journal Frontiers in Public Health. On November 28th, that article (titled “Vaccination and Health Outcomes: A Survey of 6- to 12-year-old Vaccinated and Unvaccinated Children based on Mothers’ Reports”) was removed and deleted after the journal faced widespread criticism of its methods and motives.
As reported by Retraction Watch:
The abstract — published online in Frontiers in Public Health after being accepted November 21 — reported findings from anonymous online questionnaires completed by 415 mothers of home-schooled children 6-12 years old. Nearly 40 percent of children had not been vaccinated, and those that had were three times more likely to be diagnosed with neurodevelopmental disorders such as autism, the study found.
The only statement released by Frontiers in Public Health was this brief Twitter reply to critics, which claimed that the paper had been only “provisionally” accepted despite appearing in a finalized form online:
This article was provisionally accepted but not published. In response to concerns raised, we have reopened its review.
The fact that a study alleging a link between autism and vaccines — a decades-long controversy with no mainstream scientific support and whose origins are rooted in another retracted and unethical study — was taken down at all has led some anti-vaccine groups to imply some sort of nefarious plot to hide the truth from the public.
This particular study, however, was fatally flawed on three levels: it was problematic in its design; the authors had a clear agenda combined with a financial conflict of interest; and the journal that published it is widely considered to be predatory, with a track record of publishing deeply flawed, controversial, and biased research with limited or sloppy peer-review.
First a look at the study’s design, as captured by a screenshot of its abstract before the page was removed:
Homeschool organizations in four states (Florida, Louisiana, Mississippi, and Oregon) were asked to forward an email to their members, requesting mothers to complete an anonymous online questionnaire on the vaccination status and health outcomes of their biological children ages 6 to 12. [...]
A total of 415 mothers provided data on 666 children, of which 261 (39%) were unvaccinated. Vaccinated children were significantly less likely than the unvaccinated to have been diagnosed with chickenpox and pertussis, but significantly more likely to have been diagnosed with pneumonia, otitis media, allergies and NDDs (defined as Autism Spectrum Disorder, Attention Deficit Hyperactivity Disorder, and/or a learning disability).
As ScienceBlog’s David Gorski noted on his blog Respectful Insolence, the population selected for the study is far from a representative sample (it’s a homeschool population from only four states), and 666 individuals are nowhere near enough participants from which to draw any sort of significant conclusion:
First, this survey questioned 415 mothers of 666 children educated at home. Not only is that not a representative sample, given that all the children are home-schooled, it’s not even a very big sample. [...] To find any statistically significant, much less clinically significant differences in health outcomes between vaccinated and unvaccinated children would require huge numbers.
Another critique of its methods is the fact that the study grouped autism with a series of other “neurodevelopmental disorders” (which included Attention Deficit Hyperactivity Disorder and any other learning disability) without making a distinction between these very different conditions in their results.
As bloggers and internet sleuths uncovered, this study appears to have been financially supported by individuals with an anti-vaccine agenda. A November 2012 post on the anti-vaccine blog “Age of Autism” promoted a study concept identical to the retracted study and which was to be carried out by the same research institution.
That post encouraged readers to donate to Jenny McCarthy’s anti-vaccine charity “Generation Rescue” (the post itself was written by J. B. Handey, the co-founder of that charity) and assured readers that “100%” of the money would go to the study, which it claimed was short by around 400,000 dollars:
In order to finish the work and see the first documented data comparing vaccinated and unvaccinated children, an additional $400,000 needs to be raised. [...] If you can help, please donate directly through the Generation Rescue website, HERE.
(Note: Generation Rescue is not conducting the study, we just want to see the study completed so the data can be collected and analyzed, whatever the outcome. By clicking through this donation link, you can make sure 100% of your donation goes to the study.)
In addition, over and above conflicts of interest in funding, Anthony Mawson — the study’s lead author and a visiting professor at Jackson State University — has long been a vocal proponent of the link between Autism and Vaccines. In 2007 he allegedly (according to archived webpages) wrote a letter arguing against the retraction of Andrew Wakefield’s 1998 paper that originally proposed that link — a position well outside the mainstream scientific consensus. He also alleged in a 2011 lawsuit (later dismissed) that he lost his job due to his views on vaccine safety.
Finally, the journal Frontiers in Public Health, and indeed the entire Frontiers series of journals, have exercised dubious judgement in their editorial decisions. Some reporters consider the journal to be overtly predatory — enticing fringe research with lax peer review and a pay-to-play business model.
As reported by Retraction Watch in July 2016, Frontiers in Public Health published and then retracted a study on chemtrails — the longstanding conspiracy theory about the dangers of cloud trails released from jet planes. In one of its more infamous episodes, Frontiers in Public Health published an article that questioned the link between HIV and AIDS, titled “Questioning the HIV-AIDS hypothesis: 30 years of dissent.” In response to the criticism of this controversial paper, the editors’ solution was to “reclassify” the paper from an original research paper to an “opinion paper.”
It does not appear that the peer review process was well run in this recent vaccine study either. One of the two people who peer reviewed the study was actually a chiropractor named Linda Mullin Elkins with no published research on the subject of autism or any background in vaccine research.
Frontiers in Public Health has yet to issue a formal retraction as the study’s review has been “reopened”. It is hard to see, though, how a poorly designed, limited-population study based solely on an anonymous email survey funded by organizations or individuals with an agenda, published in a journal that allows a chiropractor to review a study about the health risks of vaccines, could pass any reasonable definition of publishable.