Table 3.

Results from the external ExWAS of county-level COVID-19 mortality (till October 31, 2020) in the contiguous US.

Exposure		Transformation	Standard deviation	Phase 1						Phase 2
				Discovery set			Replication set
Variable	Category			MRR (95% CI)	p-Value	q-Value	MRR (95% CI)	p-Value	q-Value	MRR (95% CI)	p-Value
Benzidine (ug/m3)	Air toxicant	Box Cox (λ = −0.74)	4.11 × 105	0.90 (0.85, 0.95)	2.70 × 10−4	0.011	0.88 (0.83, 0.94)	6.17 × 10−5	0.003	0.92 (0.88, 0.95)	3.23 × 10−5
NO2 (ppb)	Criteria air pollutant	Yeo-Johnson (λ = −0.49)	1.25 × 10−1	1.22 (1.13, 1.32)	3.98 × 10−7	<0.001	1.25 (1.15, 1.35)	2.38 × 10−8	<0.001	1.19 (1.13, 1.26)	1.41 × 10−10
Percent previous quarter no-stat currently in service	Vacant land	log10(x + 0.001)	2.26 × 10−1	0.86 (0.81, 0.91)	2.90 × 10−7	<0.001	0.85 (0.80, 0.90)	2.56 × 10−8	<0.001	0.89 (0.85, 0.92)	1.04 × 10−8
Percent students eligible for reduced-price lunch, 2015	Food environment	No Transformation	3.71	0.88 (0.84, 0.93)	5.29 × 10−6	<0.001	0.90 (0.85, 0.95)	5.14 × 10−5	0.003	0.90 (0.87, 0.93)	6.22 × 10−9

Mortality rate ratio (MRR) and 95% confidence interval (CI) for each standard deviation increase.