Summary of COVID-19 mortality odds ratios and 95% credible intervals (CI) for a 1 μg/m3 increase in PM2.5 from additional analyses.

The first row represents our main analysis with individual-level confounders and census tract-level PM2.5 accounting for ecological and confounding bias (up to December 1, 2020). The second, third, and fourth rows represent the three additional analyses respectively: ecological regression with solely county-level data (up to December 1, 2020); Bayesian hierarchical regression with individual-level confounders and census tract-level PM2.5; and ecological regression with solely county-level data (up to June 18, 2020).