Table 1.

Definition and source of county-level variables in the study

Variable	Definition	Source
% Black residents	Percentage of residents that are non-Hispanic Black or African American.	County Health Rankings [37]
Index of concentration at the extremes (ICE) income	Represents the distribution of wealth in a population. Difference between the number of households ≥80th percentile income and the number of households ≤20th percentile income, divided by the total number of households. Values range from − 1, all households ≤20th percentile income, to 1, all households ≥80th percentile income.	United States Census Bureau [29]
% uninsured	Percentage of adults under age 65 without health insurance.	County Health Rankings [37]
% low birthweight	Percentage of live births with low birthweight, defined as < 2500 g.	County Health Rankings [37]
% adults without high school (HS) diploma	Percentage of adult residents with less than a high school diploma from 2014 to 2018.	United States Census Bureau [29]
Incarceration rate	Ratio of the total population that is in jail or prison to the total population aged 15–64 multiplied by 100.	Vera Institute of Justice [38]
% households without internet	Percentage of households reporting no internet access.	United States Census Bureau [29]
Population density (population/km2)	Population per square kilometer.	United States Census Bureau [29]
Days since first case	Number of days since the first case of COVID-19 relative to 5/10/2020.	COVID-19 Data Repository JHU [28]
Day since first death	Number of days since the first death from COVID-19 relative to 5/10/2020.	COVID-19 Data Repository JHU [28]
% over age 65	Percentage of population ages 65 and older.	County Health Rankings [37]
% obesity	Percentage of the adult population (age 20 and older) that reports a body mass index (BMI) greater than or equal to 30 kg/m2.	County Health Rankings [37]
% diabetes	Prevalence of diagnosed diabetes among Medicare beneficiaries enrolled in the fee-for-service program.	Centers for Medicare & Medicaid Services [40]
% COPD	Prevalence of diagnosed COPD among Medicare beneficiaries enrolled in the fee-for-service program.	Centers for Medicare & Medicaid Services [40]
% smokers	Percentage of adults that are current smokers.	County Health Rankings [37]
% hypertension	Prevalence of diagnosed hypertension among Medicare beneficiaries enrolled in the fee-for-service program.	Centers for Medicare & Medicaid Services [40]