Autism is just one of a number of issues where anecdotes drive public discussion about risk. Psychologist Daniel Kahneman lays out the pattern: “On some occasions, a media story about a risk catches the attention of a segment of the public, which becomes aroused and worried. The emotional reaction becomes a story in itself, prompting additional coverage in the media, which in turn produces greater concern and involvement.” Individuals or groups with an interest in driving the issue then work to keep up the flow of worrying news, and to discredit anyone who questions the hype.Tom Chivers reports at Buzzfeed:
There are hundreds of websites and Facebook pages that claim that autism is caused by vaccines, and which promote “cures” – often substances that can be bought via that website. And the stories they share are often hugely viral.
Analysis by BuzzFeed News found that more than half of the most-shared scientific stories about autism published online in the last five years promote unevidenced or disproven treatments, or purported causes.
The analysis used data from BuzzSumo, a company that tracks social sharing across multiple platforms including Facebook and Twitter, to find the most shared webpages about autism over the past five years. It then manually extracted the top 50 that claimed to present scientific or medical information about autism, such as reports on research or stories that claimed to focus on causes, or “cures”.
Those that primarily promoted a disproven or unevidenced theory about autism (for example, ones that advocated for links with vaccines or glyphosate fertiliser, or which advanced pseudoscientific cures) were classified as “unevidenced”, while those that provided an approach based on good-quality research or objective reporting were classified as “evidenced”. The categorisation erred on the side of caution, putting ambiguous or speculative articles into the “evidenced” bracket.
It found that more than half (28 out of 50, or 56%) of the most shared stories published between August 2012 and August 2017, including both of the top two, were unevidenced. Between them, the unevidenced stories were shared 6.3 million times, compared with around 4.5 million for the evidence-based stories. The top story, “Courts quietly confirm MMR vaccine causes autism”, was shared almost a million times and appears twice on the list from two different sites. As this Forbes story from 2013 explains, it is false.
The rise of social media has made it easy for these bubbles to form in recent years. But for parents of autistic children, it started much earlier – before Facebook even existed, and years before it reached its current ubiquity. Parents swapped stories via email and message boards, especially a bunch of sites on the Yahoo Health groups that sprang up in the late 1990s and early 2000s. They included places like as Environment of Harm, a Yahoo group set up to discuss “vaccine damage and mercury poisoning and other environmental toxins as it relates to autism”; GFCFKids, “a discussion forum for parents of children on the autism spectrum who are avoiding gluten and casein and other substances in their children’s diets”; Chelatingkids2, “for parents and/or family members of children with autism who are seeking biomedical intervention”; and Autism-Mercury, focusing on “the increasing incidence of autism [and] the potential link between excessive mercury exposure via thimerosal in infant vaccines”.