“In this survey study conducted among 306,799 residents aged 18 years or older across 50 US states and the District of Columbia, the proportion of individuals reporting a positive COVID-19 infection in a longitudinal nonprobability survey closely tracked the institutionally reported proportions in the US. … This study suggests that nonprobability online surveys can serve as an effective complementary method to monitor infections during an emerging pandemic and provide an alternative for estimating infections in the absence of institutional testing when at-home tests are widely available.”

Find the paper and full list of authors in JAMA Network Open.