Adapting the Index of Relative Rurality (IRR) to Estimate Rurality at the ZIP Code Level: A Rural Classification System in Health Services Research

摘要

BackgroundAccurate analysis of health problems facing rural residents depends on how rurality is defined. Health services research relies frequently on the rural urban commuting area (RUCA) codes to estimate rurality at the small area level. We modified the county-level Index of Relative Rurality (IRR) to the ZIP code level (IRRZIP) to create an alternative small-area-level rural classification system. We then compared how the 2 rural classification systems differ in how rural areas and populations are defined and in methodological analysis.