Is Country-Level Extraversion Associated with the Number of COVID-19 Cases and Deaths?

Abstract

An evolutionary explanation of between-country variation in extraversion assumes that it is more adaptive in the absence of pathogens but less adaptive in pathogen-prevalent environments. We attempted to test this assumption by correlating country-level extraversion scores and the number of COVID-19 cases and deaths. There are at least five country-level extraversion scores available, three of which were significantly correlated with the number of COVID-19 cases and two of which were significantly correlated with the number of COVID-19 deaths. This apparent partial support for the assumption is puzzling because the validity of country-level extraversion scores was low. Brief numerical simulations suggest that a statistical artefact due to combining two mutually non-independent subgroups (European/American countries and African/Asian countries) may account for the observed country-level correlations.