Researchers who analyzed a collection of mental health-related websites found a vast majority embed "an impressive number" of trackers mostly used for marketing purposes. More than a quarter embed third parties engaged in programmatic advertising and Real Time Bidding (RTB).
Eliot Bendinelli, a technologist with UK non-profit Privacy International, says the organization wanted data protection agencies to take action because it believed there was a fundamental problem with the tracking industry. Its project began with an investigation into sales in the field of ad tech companies, credit rating agencies, ad blockers, and related organizations, he says.
"We were building a case, and basically we think what they're doing is unlawful," Bendinelli continues. While waiting for agencies to act, the research team wanted to find an example of how tracking is taking place on Web pages where people go to read and share sensitive data.
"We wanted a concrete example of how tracking is happening on websites where you think you are safe, and where you are looking up or exchanging data that is sensitive and personal," he adds. They chose sites related to mental health because, as Bendinelli puts it, people may research mental health conditions online because they aren't yet ready to discuss it in person.
The World Health Organization reports 25% of the European population suffers from depression or anxiety each year, and about half of major depressions are untreated. This means every day, millions of people are researching depression online, whether it's to seek help or support someone in their lives who could be suffering from a mental health condition.
At the same time, the Internet's current business model relies on targeted advertisement to make money, tracking individuals and using their personal data to build accurate ad profiles.
To learn how these trackers follow people to mental health websites, Bendinelli and his research team analyzed 136 popular depression-related websites in France, Germany, and the UK. They used a VPN so the search results would be country-specific and began by searching terms related to depression in each of the countries' languages. They collected websites listed on the first page of search results and using a tool called Webxray, analyzed data including the number of trackers on each website, number of cookies dropped, and other analytics data.
What they found "unfortunately, was not surprising," Bendinelli says. "Google is pretty much everywhere," was a key takeaway, and he wasn't shocked to find 97% of websites analyzed had some form of Google tracker. Ninety percent had Doubleclick, which is a business owned by Google that lets online advertisers and publishers display advertisements on their websites. Right behind Google, in terms of numbers, were Facebook and Amazon trackers, he adds.
"These trackers' sole purpose was to do targeted advertising," says Bendinelli.
Real Time Bidding
More than a quarter of webpages analyzed embed third parties who engage in programmatic advertising and Real Time Bidding, a process by which ad impressions are bought and sold. When someone visits a website, a "bid request" is sent to an ad exchange. This request contains various types of data such as demographical data, location data, and browser history. The ad exchange sends this data to advertisers, who bid for the ad impression as it's presented to the site visitor. The one who bids highest will win the impression and have its ad served to users.
The problem, Bendinelli explains, is many companies are learning information the website visitors may not necessarily want to share. "It could be shared with literally hundreds of companies," he says of bid request data. While it isn't sold, it can be used for targeted ads.
Also concerning was the researchers' discovery that a small subset of websites offering depression tests would directly or indirectly share responses and results with third parties. Of the nine testing websites they found, two were storing test results and one was sending responses to another company not mentioned anywhere on the site, Bendinelli explains.
Researchers followed up with the websites they had flagged. One completely removed the test. "They realized they were doing something wrong," he notes.
Bendinelli and Frederike Kaltheuner, tech policy fellow with the Mozilla Foundation, will present more of these research findings at the Black Hat Europe 2019 conference in a briefing entitled "Is Your Mental Health for Sale?"
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