Appendix 1. Professional billing codes that did not qualify as face-to-face care.

Type of care / CPTCODE
Radiology / Starting with 7 except for 77261 – 77299
Pathology and laboratory / 8xxxx
Diagnostic procedures performed by technician / 93000, 93005, 93010,93017,93018,93025, 93040-93042, 93224-93227; 93228, 93229; 93268-93272,
Noninvasive physiology studies and procedures / 93701-93799, 93875 -93990
Vent management / 94002 – 94005
Other procedures, lab procedures or interpretation of test results / 94010 – 94799, 95250- 95251
Neuro tests likely with MD offsite interpretation only / 95812 – 95830, 95860 – 95967; 95900 – 95904; 95920 -95999, 96004- 96020
PT modalities that do not require direct pt contact of billing provider / 97010 -97028
Pt education non MD present / 98960 -98962
Telephone supervision of non-physician care / 98966-98968
Online care / 98969
Miscellaneous Services / 99000 -99091
Non-MD home health procedures / 99500-99600
Pharmacist med mgmt / 99605-99607
Category II code / Any 5-digit CPT codes that include a letter

Appendix 2. Top 50 pairs of provider specialties.

Provider 1 / Provider 2 / Number
of Pairs / Percent / Cumulative Percent
1 / Primary Care* / Primary Care / 166,468 / 6.3 / 6.3
2 / Primary Care / Obstetrics Gynecology / 141,352 / 5.4 / 11.7
3 / Primary Care / Orthopedic Surgery / 119,888 / 4.5 / 16.2
4 / Primary Care / Dermatology / 85,156 / 3.2 / 19.4
5 / Primary Care / Cardiology / 72,881 / 2.8 / 22.2
6 / Primary Care / Ophthalmology / 64,085 / 2.4 / 24.6
7 / Primary Care / Otolaryngology / 58,847 / 2.2 / 26.8
8 / Primary Care / Gastroenterology / 46,306 / 1.8 / 28.6
9 / Primary Care / Nurse Practitioner / 45,197 / 1.7 / 30.3
10 / Primary Care / Podiatry / 45,193 / 1.7 / 32.0
11 / Primary Care / Urology / 44,649 / 1.7 / 33.7
12 / Primary Care / General Surgery / 43,913 / 1.7 / 35.4
13 / Primary Care / Optometry / 33,946 / 1.3 / 36.6
14 / Primary Care / Chiropractic / 32,369 / 1.2 / 37.9
15 / Primary Care / Neurology / 31,653 / 1.2 / 39.1
16 / Obstetrics Gynecology / Orthopedic Surgery / 27,393 / 1.0 / 40.1
17 / Primary Care / Allergy Immunology / 25,491 / 1.0 / 41.1
18 / Primary Care / Pulmonary Disease / 23,612 / 0.9 / 42.0
19 / Obstetrics Gynecology / Dermatology / 23,296 / 0.9 / 42.8
20 / Primary Care / Psychiatry / 22,801 / 0.9 / 43.7
21 / Primary Care / Endocrinology / 21,450 / 0.8 / 44.5
22 / Cardiology / Orthopedic Surgery / 19,338 / 0.7 / 45.2
23 / Dermatology / Orthopedic Surgery / 18,065 / 0.7 / 45.9
24 / Primary Care / Physician Assistant / 17,095 / 0.6 / 46.6
25 / Primary Care / Neurosurgery / 16,250 / 0.6 / 47.2
26 / Primary Care / Physical Med and Rehab / 16,242 / 0.6 / 47.8
27 / Primary Care / Rheumatology / 15,398 / 0.6 / 48.4
28 / Ophthalmology / Orthopedic Surgery / 15,096 / 0.6 / 49.0
29 / Primary Care / Medical Oncology / 15,047 / 0.6 / 49.5
30 / Obstetrics Gynecology / Obstetrics Gynecology / 14,903 / 0.6 / 50.1
31 / Orthopedic Surgery / Orthopedic Surgery / 14,599 / 0.6 / 50.6
32 / Primary Care / Plastic/reconstruct surgery / 14,173 / 0.5 / 51.2
33 / Obstetrics Gynecology / Cardiology / 14,105 / 0.5 / 51.7
34 / Obstetrics Gynecology / Otolaryngology / 13,691 / 0.5 / 52.2
35 / Obstetrics Gynecology / Ophthalmology / 13,686 / 0.5 / 52.8
36 / Cardiology / Dermatology / 13,523 / 0.5 / 53.3
37 / Cardiology / Ophthalmology / 13,290 / 0.5 / 53.8
38 / Obstetrics Gynecology / Gastroenterology / 12,880 / 0.5 / 54.3
39 / Nurse Practitioner / Orthopedic Surgery / 12,777 / 0.5 / 54.7
40 / Obstetrics Gynecology / Nurse Practitioner / 12,713 / 0.5 / 55.2
41 / Primary Care / Hand Surgery / 12,414 / 0.5 / 55.7
42 / Orthopedic Surgery / Otolaryngology / 12,348 / 0.5 / 56.2
43 / Obstetrics Gynecology / General Surgery / 12,097 / 0.5 / 56.6
44 / Obstetrics Gynecology / Podiatry / 11,961 / 0.5 / 57.1
45 / Orthopedic Surgery / Podiatry / 11,557 / 0.4 / 57.5
46 / Gastroenterology / Orthopedic Surgery / 11,145 / 0.4 / 57.9
47 / General Surgery / Orthopedic Surgery / 11,028 / 0.4 / 58.3
48 / Dermatology / Ophthalmology / 10,680 / 0.4 / 58.7
49 / Orthopedic Surgery / Urology / 10,601 / 0.4 / 59.1
50 / Obstetrics Gynecology / Chiropractic / 10,089 / 0.4 / 59.5

* Primary care was defined as one of the following specialties: family practice, general practice, internal medicine, or pediatrics.