Beyond Black and White: Mapping Misclassification of Medicare Beneficiaries Race and Ethnicity

Abstract

The Centers for Medicare and Medicaid Services administrative data contains two variables that are used for research and evaluation of health disparities: the enrollment database (EDB) beneficiary race code and the Research Triangle Institute (RTI) race code. The objective of this article is to examine state-level variation in racial/ethnic misclassification of EDB and RTI race codes compared with self-reported data collected during home health care. The study population included 4,231,370 Medicare beneficiaries who utilized home health care services in 2015. We found substantial variation between states in Medicare administrative data misclassification of self-identified Hispanic, Asian American/Pacific Islander, and American Indian/Alaska Native beneficiaries. Caution should be used when interpreting state-level health care disparities and minority health outcomes based on existing race variables contained in Medicare data sets. Self-reported race/ethnicity data collected during routine care of Medicare beneficiaries may be used to improve the accuracy of minority health and health disparities reporting and research.

Keywords: Medicare; ethnicity; health disparities; minority health; race; state-level.

Figure 1.

Percentage of Medicare home health recipients (2015) whose race/ethnicity was misclassified by the EDB race (upper map) and RTI race (lower map).

Figure 2.

In every state Hispanics are misclassified by the EDB race variable (upper map) more often than by the RTI race (lower map).

Figure 3.

In every state except Montana (no change), Asians/Pacific Islanders are misclassified by the EDB race variable (upper map) more often than by the RTI race variable (lower map).

Figure 4.

Medicare beneficiaries who self-identify as American Indian/Alaskan Native (AIAN) are frequently misclassified in Medicare administrative data. The EDB and RTI race variables are nearly identical with regards to classification of AIANs, and for this reason we only present results using the RTI race variable. There is striking variation between states in the misclassification of Medicare beneficiaries in our sample who self-identify as AIAN, with nearly half of all states misclassifying 80% or more of people who self-report as AIANs, and 7 states misclassifying less than 20% (Alaska, Arizona, New Mexico, Oklahoma, Wyoming, North Dakota, and South Dakota).