by Jean Roth , jroth@nber.org , 14 Dec 2017
NBER URL: www.nber.org/data/npi.html
Source Page: http://download.cms.gov/nppes/NPI_Files.html
Source File URL: download.cms.gov/nppes/NPPES_Data_Dissemination_Dec_2017.zip
Source Text File: npidata_20050523-20171210.csv*
193200000X, Multi-Specialty Group
193400000X, Single Specialty Group