Fig. 4

Trend analysis of age-adjusted incidence rates of COVID-19: adjusted incidence rates map a displays the LISA results, indicating significant spatial clustering in the study area. High-High (HH) indicates clusters of high rates, Low-Low (LL) indicates clusters of low rates. High-Low (HL) values represent individual counties with a high rate, but are surrounded by counties with a low rate, and Low-High (LH) is its inverse. The scatter plot with Pearson’s Correlation Coefficient indicates an association with b latitude, but not c longitude