Fig. 2From: Polarized nature of the COVID-19 pandemic in Japan: associations with population age structure and behavioursPopulation density and cumulative COVID-19 cases per 100,000 population in the study areas. a Due to non-normal distribution of data, Spearman’s rank correlation test was adopted. Cumulative COVID-19 cases and cases per 100,000 population are calculated based on reported cases as of 2 May 2020Back to article page