  Web tracking technologies are pervasive and operated by a few large
technology companies. This technology, and the use of the collected data has
been implicated in influencing elections, fake news, discrimination, and even
health decisions. Little is known about how this technology is deployed on
hospital or other health related websites. The websites of the 210 public
hospitals in the state of Illinois, USA were evaluated with a web tracker
identification tool. Web trackers were identified on 94% of hospital webs
sites, with an average of 3.5 trackers on the websites of general hospitals.
The websites of smaller critical access hospitals used an average of 2 web
trackers. The most common web tracker identified was Google Analytics, found on
74% of Illinois hospital websites. Of the web trackers discovered, 88% were
operated by Google and 26% by Facebook. In light of revelations about how web
browsing profiles have been used and misused, search bubbles, and the potential
for algorithmic discrimination hospital leadership and policy makers must
carefully consider if it is appropriate to use third party tracking technology
on hospital web sites.
