COVID RADAR app: Description and validation of population surveillance of symptoms and behavior in relation to COVID-19.
Willian J van DijkNicholas H SaadahMattijs E NumansJiska Joëlle AardoomTobias N BontenMenno BrandjesMichelle BrustSaskia le CessieNiels H ChavannesRutger A MiddelburgFrits RosendaalLeo G VisserJessica Christina Kiefte-de JongPublished in: PloS one (2021)
The COVID Radar app allows voluntarily self-reporting of COVID-19 related symptoms and social distancing behaviors. Symptoms and risk behavior increase prior to a positive SARS-CoV-2 test, and user-reported case counts match closely with nationally-reported case counts in regions with high user engagement. These results suggest the COVID Radar may be a valid instrument for future surveillance and potential predictive analytics to identify emerging hotspots.