"Social media sites like Facebook offer advertisers an easy and inexpensive channel to reach narrowly-defined audiences in a relatively unregulated setting."
While much concern has been raised over Facebook's involvement in our national politics, it remains a primary source of news and information for many Americans. The possible role of Facebook, in a national health care issue, vaccinations, is explored in a new study. Spoiler alert, advertisements, especially when calibrated to the undecided, like the vaccine-hesitant, may be problematic.
The study is based on Facebook's Ad Library, "a searchable repository," of ads of national importance, part of Facebook's response to the constant drumbeat of high-level criticism. While it doesn't tell us how individuals interacted with the ads, it may offer some insights. It will not tell us how their proprietary algorithms work, but if revenue is a measure, their micro-targeted advertising works very well, to the tune of $55 billion in 2018.
The Ad Library was searched for ads for "vaccines," and data on the dates the ads ran, their titles, and the source paying for the ads was identified. Ad performance was quantified as a blend of advertisement cost along with the exposure and client engagement. As Facebook's efforts to monitor these types of ads are continually evolving, the data within the set changes over time.
With data in hand, each ad was identified by two of the authors, as pro, anti-vaccine, or irrelevant; the majority of times, when there was disagreement over the focus of the ad, it was adjudged irrelevant. The authors also sought to define significant themes within the ads. Two searches yield 505 ads, of which 309 were considered relevant – 53% pro and 47% anti.
- 90% of the ad buys cost less than $500.
- 75% of all these ads targeted "a majority (or entirely) female audience."  The audience age for the anti-vaccine ads was more concentrated on "young adults most likely to have small children."
- Pro-vaccine promotional messaging accounted for half of the ads.
- About half focused on a specific vaccine (e.g., flu) or geographic area, and was paid for by a local health care organization.
- More general ads regarding global vaccine policy accounted for an additional 24% of advertising.
- 83 buyers supported pro-vaccine messages. While roughly 40% of the total was from the Gates Foundation or Walmart, pro-vaccine ads had many sources.
- Anti-vaccine messaging described harms (49%), promoted parental choice (30%), or suggested fraud/corruption (18%). No vaccine was specified, and appeals were frequently personalized with parents describing an injury to their children.
- 27 buyers supported anti-vaccine messages, 54% of the total were purchased by two groups, the World Mercury Project and Stop Mandatory Vaccines. Overall, compared to pro-vaccine advertisements, "buys" were concentrated in a few purchasers.
It is no surprise that the advertising varied messages to differing groups – that is the purpose of microtargeted ads. The researcher's data also showed that while equal percentages of pro and anti-vaccine ads were taken down by Facebook, it was rarely over content, it was about a lack of attribution of the buyer.
The Town Square
In Facebook's town square, you can speak if you have a name. But as the researchers point out, a name can be misleading. Is the National Vaccine Information Center pro or anti-vaccine, or it is merely a fair witness.  More importantly, they believe we are witnessing the rise of what economists would call a complementary industry, using Facebook's advertising as a way to sell controversy – in this instance, over vaccinations. Fear continues to sell.
In a real town square, you can see your opposition and confront them in real-time. You even have the option of walking away. The town square of social media masks identity, and even if you want to respond, it is asynchronous, resulting in competing monologues more than dialogue. And the algorithms make it so difficult to walk away; they just keep serving up the same content over and over again.
 This is in keeping with the acknowledged role of women as the gatekeepers of healthcare for their families.
 While it may sound vaguely federal, it is "a non-profit advocacy group opposed to vaccination with a long history of controversial lobbying."
Source: Vaccine-related advertising in the Facebook Ad Archive Vaccine DOI: 10.1016/j.vaccine.2019.10.066