Sex, age, and race/ethnicity were ascertained from death certificates as originally recorded by funeral directors. In line with the US Census, we categorized race/ethnicity as follows: non-Latino white, non-Latino black, Latino, Asian and Pacific Islander (API), and AIAN.11 Death certificate and census data collect ethnicity information using the category Spanish/Hispanic/Latino; we used the term Latino for this category. County-level SES was examined using data from the American Community Survey (2011-2015). These variables included unemployment percentage (ie, percentage of civilians aged ≥16 years in the labor force who are unemployed), percentage of population aged 25 years or older with a bachelor’s degree, and median household income in the past 12 months, measured in 2015 inflation-adjusted dollars. Variables were classified into quintiles according to their distribution across counties, by county population size, as described previously.12 We also examined rurality by categorizing counties using the 2013 Rural-Urban Continuum codes developed by the US Department of Agriculture.13
