The project described in this article develops a comprehensive, public database of U.S. individual healthcare providers from 1999 to 2025 ("Provider Database"). We combine data from multiple sources: NPPES (National Plan and Provider Enumeration System), ResDAC Unique Physician Identification Number Directory (UPIN Directory), Medicare Carrier files; PECOS (Medicare Provider Enrollment, Chain, and Ownership System), MD-PPAS (Medicare Data on Provider Practice and Specialty), DEA (Drug Enforcement Administration), and physician vertical integration data. The database covers 7 million providers, including 1.36 million physicians, covers the 2007 switch from UPIN to National Provider Identifier (NPI), and includes 918,609 NPI-UPIN pairs. Side public databases track providers' zip code and physician integration status over time. Side non-public databases (available to researchers with Carrier file access) include providers' Medicare provider identification number and tax identification number. This article details the database methodology and illustrates its use in studying trends in provider supply, over time and across states, and physician integration.
Chorniy et al. (Thu,) studied this question.