Table 3 Estimates effects of long-term PM_2.5 exposure and Temperature on COVID-19 mortality rate using the negative binomial regression model, adjusted for all potential confounders (From 01 May to 31 December, 2020)

Annual average Long-term PM_2.5 exposure (μg/m³)

1.244^a (1.083–1.428)

1.258^b (1.104–1.434)

1.264^b (1.111–1.439)

1.267^b (1.114–1.442)

1.271^b (1.118–1.444)

1.258^b (1.111–1.423)

1.151^b (1.036–1.279)

1.078 (0.985–1.180)

1.090 (0.999–1.190)

Annual average Temperature over 12 years

0.916 (0.829–1.012)

0.913 (0.832–1.002)

0.913 (0.832–1.001)

0.914 (0.834–1.002)

0.917 (0.837–1.004)

0.921 (0.844–1.005)

0.905^b (0.840–0.974)

0.870^b (0.816–0.927)

0.859^b (0.807–0.914)

Number of intensive care and resuscitation beds (per 100,000)

1.025^a (1.002–1.049)

1.020 (0.999–1.042)

1.019 (0.998–1.041)

1.018 (0.997–1.040)

1.018 (0.997–1.039)

1.015 (0.995–1.036)

1.011 (0.994–1.029)

1.003 (0.988–1.018)

1.006 (0.991–1.020)

Medical density (per 100,000)

0.998 (0.995–1.000)

0.999 (0.996–1.001)

0.999 (0.997–1.001)

0.999 (0.997–1.001)

0.999 (0.997–1.001)

1.000 (0.997–1.002)

1.000 (0.998–1.002)

1.001 (0.999–1.002)

1.001 (0.999–1.002)

% People aged 60 or more

1.088^b (1.021–1.158)

1.096^b (1.032–1.163)

1.097^b (1.034–1.164)

1.100^b (1.037–1.167)

1.097^b (1.035–1.163)

1.096^b (1.036–1.159)

1.046 (0.999–1.095)

1.037 (0.997–1.080)

1.039 (0.999–1.080)

% Males

1.467 (0.995–2.164)

1.521^a (1.050–2.203)

1.557^a (1.079–2.248)

1.589^a (1.102–2.291)

1.585^a (1.103–2.277)

1.571^a (1.106–2.233)

1.482^a (1.098–1.999)

1.331^a (1.025–1.730)

1.310^a (1.015–1.690)

% Unemployment

1.011 (0.872–1.173)

0.996 (0.866–1.145)

0.997 (0.868–1.145)

0.997 (0.868–1.145)

1.001 (0.873–1.148)

0.974 (0.854–1.110)

0.987 (0.883–1.105)

0.989 (0.897–1.091)

0.990 (0.899–1.090)

Rate of Poverty (per cent)

0.999 (0.904–1.104)

1.006 (0.916–1.105)

1.009 (0.920–1.107)

1.010 (0.921–1.108)

1.009 (0.921–1.106)

1.026 (0.940–1.120)

1.023 (0.948–1.103)

1.018 (0.953–1.087)

1.017 (0.954–1.084)

% Urban population (proportion of people living in the great urban areas)

1.021^b (1.006–1.037)

1.021^b (1.007–1.036)

1.021^b (1.007–1.036)

1.022^b (1.008–1.037)

1.021^b (1.007–1.036)

1.023^b (1.009–1.036)

1.013^a (1.002–1.024)

1.011^a (1.002–1.020)

1.008 (0.999–1.017)

Population density (inhab/square)

1.000 (1.000–1.000)

1.000 (1.000–1.000)

1.000 (1.000–1.000)

1.000 (1.000–1.000)

1.000 (1.000–1.000)

1.000 (1.000–1.000)

1.000 (1.000–1.000)

1.000 (1.000–1.000)

1.000 (1.000–1.000)

Standardized Prevalence of Diabetes (%)

1.160 (0.772–1.742)

1.136 (0.775–1.666)

1.138 (0.779–1.661)

1.134 (0.777–1.653)

1.125 (0.775–1.633)

1.126 (0.785–1.614)

1.187 (0.871–1.619)

1.216 (0.930–1.589)

1.188 (0.916–1.542)

Criteria for assessing goodness of fit:

 Deviance

1.1594

1.1835

1.1859

1.1882

1.1841

1.1897

1.1574

1.171

1.1661

 Scaled Deviance

1.1594

1.1835

1.1859

1.1882

1.1841

1.1897

1.1574

1.171

1.1661

 Pearson Chi-Square

1.3409

1.2943

1.2899

1.2881

1.2894

1.2474

1.2029

1.1794

1.2021

 Scaled Pearson X2

1.3409

1.2943

1.2899

1.2881

1.2894

1.2474

1.2029

1.1794

1.2021

 BIC (smaller is better)

731.9157

765.3375

771.5867

774.6766

776.8832

784.2321

805.7196

879.2935

924.3351