Table 1Â The definitions and sources of the 12 selected risk factors, and the literature supporting these factors
From: Risk factors associated with mortality of COVID-19 in 3125 counties of the United States
Category | Variable | Description | Source | Related topics | Previous studies |
|---|---|---|---|---|---|
Health behaviors | With access to exercise opportunities (%) | Percentage of population with adequate access to locations for physical activity | Business Analyst, Delorme map data, ESRI, & US Census Tigerline Files | Social Distancing; Outdoor and indoor exercise | Novel |
Insufficient sleep (%) | Percentage of adults who report fewer than 7Â h of sleep on average | Behavioral Risk Factor Surveillance System | Immune system | Novel | |
Clinical care | Primary care physicians ratio | Ratio of population to primary care physicians | Area Health Resource File/American Medical Association | Medicare services | Novel |
Social and economic factors | Segregation index-non-Whites/Whites | Index of dissimilarity where higher values indicate greater residential segregation between non-White and White county residents | American Community Survey, 5-year estimates | Poor health status | Novel |
Physical environment | Long commute—drives alone (%) | Among workers who commute in their car alone, the percentage that commute more than 30 min | American Community Survey, 5-year estimates | Psychological risks | Novel |
Drive alone to work (%) | Percentage of the workforce that drives alone to work | American Community Survey, 5-year estimates | Psychological risks | Novel | |
Average daily PM2.5 (mg/m3) | Average daily density of fine particulate matter in micrograms per cubic meter (PM2.5) | Environmental Public Health Tracking Network | Air quality | E Conticini, B Frediani and D Caro [10] D Contini and F Costabile [31] L Martelletti and P Martelletti [32] | |
Demographics | Population | Resident population | Census Population Estimates | Population densities | Novel |
Rural (%) | Percentage of population living in a rural area | Census Population Estimates | Demographical science | Novel | |
Hispanic (%) | Percentage of population that is Hispanic | Census Population Estimates | Minorities | Novel | |
Female (%) | Percentage of population that is female | Census Population Estimates | Sex | C Wenham, J Smith and R Morgan [33] | |
65 and over (%) | Percentage of population ages 65 and older | Census Population Estimates | Age structure | G Onder, G Rezza and S Brusaferro [11], AS Abdulamir and RR Hafidh [34] |