Table 1: Prescriber Characteristics among Metformin-Prescribing Clinicians Prescribing sodium-glucose cotransporter 2 inhibitors (SGLT2i) over time.

The table includes metformin-prescribing clinicians that also prescribe SGLT2i for each category, with each cell representing numerator counts and percentages. The denominator of the prescriber counts for metformin-prescribing clinicians are included in Supplemental Table II.

	2014	2015	2016	2017	2018
Number of Prescribers	9048 (4.3)	24628 (11.3)	34106 (15.1)	40640 (17.7)	45255 (19.5)
Specialty
Cardiology	47 (1.1)	137 (3.6)	194 (5.5)	294 (8.9)	420 (13.7)
Endocrinology	1452 (32)	2604 (55.5)	2955 (60.7)	3348 (66.7)	3681 (71.6)
Family Practice	2902 (3.8)	9042 (11.8)	12819 (16.6)	15203 (19.6)	16544 (21.4)
Internal Medicine	3224 (5.1)	8398 (13.3)	11157 (17.7)	13028 (20.9)	14230 (23.3)
Other	1423 (2.2)	4447 (6.3)	6981 (9.1)	8767 (10.7)	10380 (12.1)
Region
Midwest	1758 (3.7)	5136 (10.4)	7254 (14.4)	8680 (16.9)	9857 (19)
Northeast	1972 (4.5)	4849 (10.9)	6701 (14.5)	8191 (17.5)	9284 (19.7)
South	3771 (5.1)	10700 (14.1)	14761 (18.9)	17279 (21.7)	18610 (23.1)
West	1547 (3.2)	3943 (8)	5390 (10.6)	6490 (12.5)	7504 (14.2)
Graduation Year
< 1980	1180 (6.5)	2882 (16)	3723 (20.9)	4335 (24.5)	4612 (26.6)
1980 – 1989	2367 (6.9)	5980 (17.3)	7868 (22.9)	9063 (26.6)	9784 (29)
1990 – 1999	2368 (5.5)	6321 (14.6)	8625 (19.9)	10258 (23.6)	11044 (25.5)
2000 – 2009	1428 (3.7)	4395 (11.1)	6366 (15.7)	7632 (18.6)	8848 (21.5)
2010 – 2018	177 (1.1)	949 (4.1)	2164 (7.1)	3535 (9.4)	5132 (11.9)
School
Non-US MD	2647 (6.2)	6884 (13.7)	9405 (18.0)	11382 (21.2)	12750 (23.7)
US MD/DO	4252 (5.4)	11398 (14.2)	15637 (19.1)	18584 (22.4)	20729 (24.8)
NP/PA	1006 (2.4)	3394 (7.0)	5538 (10.3)	7058 (12.0)	8499 (13.4)

Abbreviations: DO: Doctor of Osteopathic Medicine, MD: Doctor of Medicine, NP: Nurse Practitioner, PA: Physician Assistant