NCT05080179

Impact of Nudges on Downloads of COVID-19 Exposure Notification Smartphone Apps: A Randomized Trial

Completed NA Results posted Last updated 28 August 2023

What this trial tests

NA trial testing Self-Benefit/Social Norm in COVID-19 in 16,903 participants. Completed in 28 January 2021.

Timeline

11 December 2020

Primary endpoint
28 January 2021

28 January 2021

Quick facts

Lead sponsor	University of Pennsylvania
Phase	NA
Status	Completed
Study type	INTERVENTIONAL
Allocation	randomized
Design	factorial
Masking	single
Primary purpose	treatment
Enrollment	16,903
Start date	11 December 2020
Primary completion	28 January 2021
Estimated completion	28 January 2021
Sites	1 location across United States

Drugs / interventions tested

• Self-Benefit/Social Norm
• Self-Benefit/No Social Norm
• Other Benefit/Social Norm
• Other Benefit/No Social Norm

Conditions studied

• COVID-19 — all drugs for COVID-19 →

Sponsor

University of Pennsylvania

Who can join

Eligibility, any sex, with COVID-19. Patients with the condition only — healthy volunteers not accepted.

Results — posted to ClinicalTrials.gov

Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.

Click on Link to Download COVID Alert PA App Primary · 48 days

The investigators measured choice to click on the link to download the COVID Alert PA app or not, conditional on opening the email. Because participants may not immediately open their e-mail, or may return to the e-mail to click the link, we allowed for a period of approximately 7 weeks or 48 days from date of initial e-mail for completion of outcome measure.

Number opened e-mail

Group	Value	95% CI
Self-Benefit/Social Norm	4232
Self-Benefit/No Social Norm	4246
Other Benefit/Social Norm	4211
Other Benefit/No Social Norm	4214

Number clicked link

Group	Value	95% CI
Self-Benefit/Social Norm	353
Self-Benefit/No Social Norm	380
Other Benefit/Social Norm	355
Other Benefit/No Social Norm	744

Sponsor's own description

Eligible participants who were active beneficiaries of a large insurer living in Pennsylvania were sent an email encouraging them to download the contact tracing app in Pennsylvania, COVID Alert PA.

Participants will be randomly assigned to one of four conditions in a 2 (Self-benefit vs. Other-Benefit) x 2 (Social Norms Present vs. Social Norms absent) design.

All participants received an email that said :

"COVID Alert PA is the official Exposure Notification App from the Pennsylvania Department of Health. Join Penn Medicine in the fight against COVID-19 and download COVID Alert PA today!"

---Investigators manipulated the content here---

"The app uses Bluetooth to sense when one person is in close contact with another person with the app. If someone tests positive for COVID-19, and they decide to upload the information to the health department, people who have the app and who have been in contact with them will be alerted.

If you are interested in downloading the app, please click COVID Alert PA. We appreciate you joining our efforts. Together we can beat COVID-19!"

In the Other-Benefit condition, it said: "It can help you reduce your risk of unknowingly spreading the virus to your friends, family, and larger community."

In the Self-Benefit condition, it said: "It can help you determine where and when to get testing, and how to get care if you need it."

In the Social Norms Present condition, it said: "Over 650,000 Pennsylvanians have already downloaded the app!"

In the Social Norms Absent condition, it said the statement about social norms above.

Participants who do not open the initial email received a follow-up email.

Publications & conference data

1 peer-reviewed publication reference this trial (live from Europe PMC):

1. Effect of Nudges on Downloads of COVID-19 Exposure Notification Apps: A Randomized Clinical Trial.
   Sharif MA, Dixon E, Bair EF, Garzon C, et al · · 2021 · cited 2× · PMID 34940870 · DOI 10.1001/jamanetworkopen.2021.40839