Overview of Master Individual Provider Crosswalk

We have developed a “Master Individual Provider Crosswalk,” which includes a variety of provider information for individual providers (not institutions), over 1999-2016, including all available identifiers (National Provider Identifier (NPI), Unique Physician Identification Number (UPIN), Medicare Provider Identification Number (PIN), Drug Enforcement Administration (DEA) number, up to five state license numbers), name, location (by year), gender, and specialty. The principal provider types are physicians, nurse practitioners (NPs) and physician assistants (PAs).

One goal of the crosswalk is to create a bridge between UPIN (used through 2006) and NPI (used starting 2007). To date, there is no comprehensive crosswalk between these two identifiers, making analyses using physician information over an extended period of time incomplete. The NBER UPIN-NPI crosswalk only uses NPPES to generate their dataset and they misclassify some identifiers as UPINs, which are different identifiers but have the UPIN format. Another goal is to map provider location over time. The crosswalk includes: (i) complete address with zip code from NPPES; (ii) zip code from the ResDAC UPIN directory; and (iii) the zip code where the provider saw the most patients in the Carrier file for each year.

This information is compiled from: (i) NPPES (National Plan and Provider Enumeration System) records since inception of NPPES in 2007; (ii) a UPIN directory compiled by ResDAC annually during 2003-2007; (iii) Medicare claims data (the 5% national Medicare random sample) over 1999-2016 (the “Carrier” file, which includes all claims by individual providers); (iv) an NPI-DEA directory available from 2010-2012, initially prepared by CMS.

Our Master Individual Provider Crosswalk has 5,383,037 records including 1,648,890 distinct NPIs (unique providers), including all providers who provide services in the Medicare Carrier file. Of these, 838,873 (51%) are physicians, and 243,069 (15%) are NPs or PAs. One provider has a unique NPI, may have a unique UPIN, can have more than one Medicare PIN, and more than one DEA number.

Of the ~1.65M providers in the Crosswalk: 892,386 have UPIN; 1,466,815 have at least one Medicare PIN (most have more); 857,292 have all three main identifiers (NPI, UPIN and Medicare PIN) – these providers with three identifiers account for ~78% of the Carrier file claims for 2000, and ~54% in 2016; 873,936 have at least one DEA number.