Google search histories of patients presenting to an emergency department: an observational study

To test patients' willingness to share and link their prior Google search histories with data from their electronic medical record (EMR), and to explore associations between search histories and clinical conditions.

Cross-sectional study of emergency department (ED) patients from 2016 to 2017.

Academic medical centre ED.

A total of 703 patients were approached; 334 of a volunteer sample of 411 (81%) reported having a Google account; 165 of those (49%) consented to share their Google search histories and EMR data; 119 (72%) were able to do so. 16 (13%) of those 119 patients had no data and were not included in the final count. Patients under the age of 18 or with a triage level of 1 were considered ineligible and were not approached.

Health relatedness of searches in the remote past and within 7 days of the ED visit, and associations between patients' clinical and demographic characteristics and their internet search volume and search content.

The 103 participants yielded 591 421 unique search queries; 37 469 (6%) were health related. In the 7 days prior to an ED visit, the percentage of health-related searches was 15%. During that time, 56% of patients searched for symptoms, 53% for information about a hospital and 23% about the treatment or management of a disease. 53% of participants who used Google in the week leading up to their ED visit searched for content directly related to their chief complaint.

Patients were willing to allow researchers simultaneous access to their Google search histories and their EMR data. The change in volume and content of search activity prior to an ED visit suggests opportunities to anticipate and improve health care utilisation in advance of ED visits.