Table 1.
Summary characteristics of study population, ambient exposures and neighborhood contextual factors
| Characteristics | Levels |
|---|---|
| Total admissions a, No. (%) | 1,211,100 (−) |
| Arizona | 77,355 (6.4) |
| Maryland (after 2009) | 64,231 (5.3) |
| Michigan | 176,521 (14.6) |
| New York | 521,710 (43.1) |
| New Jersey (after 2008) | 122,676 (10.1) |
| North Carolina | 153,123 (12.6) |
| Rhode Islands | 31,309 (2.6) |
| Washington | 64,175 (5.3) |
| Zip codes covered (>100 residents) | 6,529 |
| Study period | 2002–2016 |
| Age, No. (%) | |
| Children (age<=9 yrs.) | 1,741 (0.1) |
| Adolescents (10–19 yrs.) | 53,441 (4.4) |
| Young Adults (20–29 yrs.) | 240,495 (19.9) |
| Adults (30–64 yrs.) | 809,470 (66.8) |
| Elderly (>=65 yrs.) | 105,919 (8.7) |
| Other unidentified | 34 (0.0) |
| Sex, No. (%) | |
| Male | 698,781 (57.7) |
| Female | 512,275 (42.3) |
| Other unidentified | 44 (0.0) |
| Race/Ethnicity, No. (%) | |
| Non-Hispanic black | 391,924 (32.4) |
| Non-Hispanic white | 505,256 (41.7) |
| Other combined racesb | 179,247 (14.8) |
| Other unidentifiedc | 134,673 (11.1) |
| Neighborhood contextual factors, median (IQR) | |
| Poverty rate, % | 7.5 (4.4, 12.2) |
| High school or less education, % | 22.0 (13.5, 32.9) |
| Ambulatory visits per year per 100 population | 80.0 (76.3, 83.0) |
| Population density, people per mile2 | 107.9 (24.2, 895.2) |
| Smoking rated, % | 0.48 (0.44, 0.52) |
| ICEwbincomee | 0.18 (0.09, 0.30) |
| Ambient annual exposures, median (IQR) | |
| Fine particulate matter (PM2.5), μg/m3 | 9.0 (7.3, 10.8) |
| Nitrogen dioxide (NO2), ppb | 15.8 (10.5, 25.1) |
| Temperature, °C | 10.6 (9.0, 13.3) |
| Cumulative precipitation, m | 1.2 (1.0, 1.3) |
Total admissions included in this table are primary admissions we used for this study after restriction criteria (described in Methods, Data Source & Study Population);
Other combined races include Asians/Pacific Islanders, Hispanic/Latino, Native Americans and other races;
Other unidentified includes admissions without information on race/ethnicity (In particular, Washington state does not provide information on race/ethnicity);
ZIP code level smoking rate, data source: CDC The Behavioral Risk Factor Surveillance System (BRFSS).
Index of Concentration at the Extremes (high income white households versus low income black households*), data source: Krieger N, Chen JT, Waterman PD. Using the methods of the Public Health Disparities Geocoding Project to monitor COVID-19 inequities and guide action for social justice. Available as of May 15, 2020 at: https://www.hsph.harvard.edu/thegeocodingproject/covid-19-resources