Berkeley Unified Numident Mortality Database: Public administrative records for individual-level mortality research

Background: While much progress has been made in understanding the demographic determinants of mortality in the United States using individual survey data and aggregate tabulations, the lack of population-level register data is a barrier to further advances in mortality research. With the release of Social Security application (SS-5), claim, and death records, the National Archives and Records Administration (NARA) has created a new administrative data resource for researchers studying mortality. We introduce the Berkeley Unified Numident Mortality Database (BUNMD), a cleaned and harmonized version of these records. This publicly available dataset provides researchers access to over 49 million individual-level mortality records with demographic covariates and fine geographic detail, allowing for high-resolution mortality research. Objective: The purpose of this paper is to describe the BUNMD, discuss statistical methods for estimating mortality differentials based on this deaths-only dataset, and provide case studies illustrating the high-resolution mortality research possible with the BUNMD. Methods: We provide detailed information on our procedure for constructing the BUNMD dataset from the most informative parts of the publicly available Social Security Numident application, claim, and death records. Contribution: The BUNMD is now publicly available, and we anticipate these data will facilitate new avenues of research into the determinants of mortality disparities in the United States.