Skip to main content
. Author manuscript; available in PMC: 2023 Jun 2.
Published in final edited form as: Environ Res. 2022 Nov 2;216(Pt 3):114684. doi: 10.1016/j.envres.2022.114684

Table 1.

Descriptive statistics of all US Medicare fee-for-service beneficiaries aged >65 living in the contiguous US.

Demographics at study entry

Individual-level covariates N (%)

Sex
 Female 33,985,877 (55.2)
 Male 27,626,594 (44.8)
Age
 65–74 years 47,199,810 (76.6)
 75–84 years 10,571,973 (17.2)
 85+ years 3,840,688 (6.2)
Race
 White 51,998,567 (84.4)
 Black 5,418,919 (8.8)
 Other/unknown 4,194,985 (6.8)
Medicaid Eligibility
 Not eligible 53,950,444 (87.6)
 Eligible 7,662,027 (12.4)
Aggregated data (2000–2016) a
Zip code-level covariates Median (IQR)
Temperature
 Summer average temperature (◦ C) 29.8 (5.2)
 Winter average temperature (◦C) 8.4 (11.8)
US census covariates
 Population density (persons/mile2) 629.5 (3068.4)
 Median home value ($1000) 144.3 (148.4)
 Median household income ($1000) 46.6 (25.3)
 % with less than a high school degree 24.5 (21.4)
 % below the poverty level 8.5 (8.0)
 % owner-occupied housing units 71.4 (21.9)
 % Black 3.9 (13.7)
 % Hispanic 5.3 (14.3)
BRFSS covariates
 % ever smoked 46.2 (9.1)
 Average BMI 27.4 (1.3)
Other environmental exposures
 Summer average max relative humidity (%) 90.3 (10.9)
 Winter average max relative humidity (%) 86.0 (9.4)
a

Descriptive statistics of the zip code level covariates are given for the strata (aggregated data based on zip code, year, sex, race, Medicaid eligibility, 2-year categories of age at study entry and year of follow-up).