BACKGROUND: The Northwest Tribal Registry (NTR) is a database of American Indian/Alaska Native (AI/AN) patients treated by Indian Health Service (IHS), Tribal, and Urban Indian Health clinics in Idaho, Oregon, and Washington. NTR is compiled by using IHS Resource and Patient Management System (RPMS) electronic health record (EHR) data. Because Tribal clinics can adopt non-RPMS EHRs, NTR is less able to detect racial misclassification in state databases, including death certificate data. Underestimation of disease in the AI/AN population affects prioritization of health concerns, prevention efforts, and funding allocation. We assessed whether updating NTR by using the IHS General Data Mart (GDM), which contains user population data from IHS, Tribal, and Urban Indian Health clinics regardless of which EHR is used, improves accuracy of AI/AN race classification in Washington state death certificates.
METHODS: To identify death certificates with misclassified AI/AN race, we conducted 2 probabilistic record linkages with 2012–2014 Washington state death certificate data; 1 with the RPMS-generated NTR and 1 with the GDM-generated NTR. We compared number of sites and records, linkage matches, and percent misclassification of AI/AN race.
RESULTS: The GDM-generated NTR included more sites (46 versus 34) and more AI/AN persons (231,060 versus 180,794) than the RPMS-generated NTR. The GDM-generated NTR resulted in more linkage matches, compared with the RPMS NTR (243 versus 183) and identified more records with misclassified race among Washington state death certificates, compared with the RPMS-compiled NTR (7.4% [243/3,270] versus 5.7% [183/3,210]).
CONCLUSIONS: The GDM-generated NTR might increase reporting accuracy for AI/AN race and AI/AN morbidity and mortality in state databases. We recommend the IHS GDM be considered as the source of NTR updates.