Contextual factors and the COVID-19 outbreak rate across U.S. counties in its initial phase

Abstract

Background: This study examines the association of contextual factors with the COVID-19 outbreak rate across U.S. counties in its initial phase. Methods: Contextual factors are simultaneously tested at the county- and state-level with a multilevel linear model using full maximum likelihood. Results: The variation between states is substantial and significant (ICC = 0.532, u0 = 8.20E−04, P