Study setting, participants, and payment collection
This serial cross-sectional study examined the magnitude and trends in industry payments to endocrinologists since the inception of the Open Payments Database. Starting August 1, 2013, the Sunshine Act mandated all pharmaceutical manufacturers, medical device manufacturers, and group purchasing organizations to disclose financial transfers to physicians in the Open Payments Database, which include three major types: general, research, and ownership payments. General payments included acquisitions (since 2021), charitable contributions, speaker fees, consulting fees, debt forgiveness (since 2021), education, entertainment, food and beverages, gifts, honoraria, long-term medical supply or device loans (since 2021), royalties and licenses, and travel and lodging. All categories of general payments were considered in this study, as this study aimed to evaluate overall size of the endocrinologists-industry financial relationships. As the 2013 data are partial disclosure of payments between August and December 2013, this study considered general and research payments provided to endocrinologists between 2014 and 2022. The analyses did not include data from ownership and investment payment files that are separately disclosed from the general payment files in the Open Payments, as these datasets contain information of status of ownership interests or stocks of healthcare companies hold by physicians each year. Therefore, these datasets do not indicate the transfer of payments. Meanwhile, general payment files contain information of transfer of payments made to physicians by healthcare industry including payments for ownership interests. Research payments include research costs such as medication supply and equipment used in clinical trials. Detailed definitions of each payment category and variables used for analysis in this study are described in Supplemental Material 1 and available on the Open Payments Database webpage (13).
This study defined endocrinologists as physicians whose primary specialty was “Allopathic & Osteopathic Physicians|Internal Medicine|Endocrinology, Diabetes & Metabolism” (health care provider taxonomy code: 207RE0101X) in the National Plan and Provider Enumeration System (NPPES) and extracted National Provider Identifier (NPI) numbers for all physicians classified as endocrinologists from the NPPES database which was last updated on April 9, 2023. All general and research payments data were downloaded from the Open Payments Database between 2014 and 2022 (14) and extracted all general and research payments they received between January 2014 and December 2022 matching their NPI number. Payment datasets in 2014-2015 were archived as of July 2023, but were downloadable from the Open Payments Database webpage (14). Before data analysis, the contents and nature of individual general payments over $100,000 were checked by the corresponding author to exclude potential errors in these large payments. Three consulting fees and two compensation fees were recategorized as ownership payments, as these payments were made to an endocrinologist as registered stock units for compensations (Supplemental Material 2). The study excluded 2013 payments from this study, as these payments only represented August-December. Most research payments came indirectly via teaching hospitals and other third parties. Including only direct research payments to individual physicians leads to underestimating their magnitude (15,16); therefore, both associated research payments and direct research payments were included in this study (17-19). Associated research payments include any funding for research where the physician is a primary investigator. Direct research payments are those provided directly to the recipient. Of 9164 active endocrinologists registered in the NPPES, 1162 were newly activated after January 2014 and were excluded from the study sample. Therefore, 8002 endocrinologists were included in this study. The NPPES database only includes information for active physicians and does not include physicians who are currently deactivated due to death or retirement: thus, endocrinologists who were deactivated as of April 9, 2023, were not included in this study.