METHODS: The adjusted Chiang II method was chosen by the SCALE Workgroup, and LE estimates were calculated using five years of mortality to increase the stability of sub-county estimates. In Florida, the most recent years of geocoded death certificate data available were 2009 through 2013. We considered using both American Community Survey five-year estimates (2009-2013) and 2010 Decennial Census as denominator data. We also compared LE estimates using the standard age categorization scheme and collapsing the first two age categories (less than 1 year and 1 to 4 years) into one group. Exclusions were made based on large standard errors (SE; i.e., >2) and small populations (i.e., <10,000).
RESULTS: We ultimately chose 2010 Decennial Census for denominator data based on the availability of population counts for single years of age by gender and race/ethnicity. After ZIP code-level exclusions were made, LE varied from a median of 78.86 years (range: 68.47 – 90.22) overall to a median of 76.38 years (64.24 – 85.56) for males and 81.43 years (72.12 – 93.49) for females. More variability was seen by race/ethnicity, with LE ranging from 75.67 years (63.16 – 90.86) for African Americans to 82.59 years (75.41 – 90.66) for Hispanics. Finally, LE estimates exhibited a small but significant difference when the youngest age groups were collapsed for calculations (mean difference = 0.02 years, p-value = 0.01).
CONCLUSIONS: LE varies greatly by gender and race/ethnicity overall and across ZIP codes in Florida. We choose to calculate LE at the ZIP code level so that estimates matched the geographic scale of many of Florida’s other health indicators. Despite well-known issues with using ZIP codes (e.g., changing boundaries), consistency across indicators and the availability of a variety of social determinants of health data at this geographic level will allow for more in-depth investigation into health disparities by place among Florida residents. Next steps include assessing the relationship between social determinants and LE and incorporating this data into community health assessments and targeted interventions throughout the state.