JMIR Publications

ABSTRACT

Background:

During periods of high COVID-19 incidence, United States (U.S.) health departments were unable to scale up case management staff to deliver effective and timely contact tracing services. New digital contact tracing (DCT) interventions were deployed quickly during the pandemic without an opportunity to conduct experiments to determine effectiveness.

Objective:

To evaluate the effectiveness of COVID-19 DCT applications deployed in the U.S. during the COVID-19 pandemic. Case investigation and contact tracing are core public health tools used to interrupt disease transmission, but it is unclear whether current DCT applications can effectively supplement understaffed manual contact tracers.

Methods:

There are no clearly established assessment methods for public health applications offered by the US National Library of Medicine (NLM) National Information Center on Health Services Research and Health Care Technology (NICHSR), nor the Food and Drug Administration (FDA). Therefore, we evaluated COVID-19 digital contact tracing applications by adapting the American Psychological Association (APA) App Evaluation Model (AEM) framework. We used data from a nationally representative survey of COVID-19 related behaviors and experiences. A minimum critical mass measure is threshold is used to assess population effectiveness (56%). Logistic regression analyzed characteristics of segments adopting and interested in DCT applications.

Results:

A total of 17.4% (n=490) of the study population reported adopting a DCT application, 24.7% (n=697) reported interest, and 58.0% (n=1637) were not interested. Younger, high income, and uninsured individuals were more likely to adopt a DCT application. In contrast, people in fair to poor health were interested in DCT applications but did not adopt them. Application adoption was positively associated with visiting friends and family outside the home (OR 1.63 95%CI 1.28-2.09), not wearing masks (OR 0.52 95% CI 0.38-0.71), and adopters thinking they have or had COVID-19 (OR 1.60 95% CI 1.21-2.12).

Conclusions:

Overall, a small segment of the population adopted DCT applications. These applications may not be effective in protecting adopter’s friends and family from their maskless contacts outside the home given low adoption rates and DCT technology false negative detection issues. Public health community should account for user behavioral factors in application design.