| Nurse practitioner | 53 |
| Family practice | 46 |
| Internal medicine | 43 |
| Physician assistant | 33 |
| Psychiatry | 29 |
| Emergency medicine | 24 |
| Physical therapist (private practice) | 21 |
| Clinical psychologist | 20 |
| Obstetrics/gynecology | 17 |
| Certified Registered Nurse Anesthetist (CRNA) | 17 |
| Optometrist | 16 |
| Anesthesiology | 15 |
| Registered Dietician/Nutrition Professional | 13 |
| Chiropractic | 12 |
| Licensed clinical social worker | 11 |
| General surgery | 10 |
| Ophthalmology | 10 |
| Podiatry | 10 |
| Dermatology | 9 |
| Diagnostic Radiology | 8 |
| Neurology | 7 |
| Marriage and Family Therapist | 7 |
| Cardiology | 6 |
| Orthopedic surgery | 6 |
| Mass Immunization Roster Billers | 5 |
| Otolaryngology | 5 |
| Occupational therapist (private practice) | 5 |
| Hospitalist | 5 |
| Physical medicine and rehabilitation | 5 |
| Nephrology | 5 |
| Pain Management | 4 |
| Plastic and reconstructive surgery | 4 |
| Gastroenterology | 4 |
| Ambulatory Surgical Center | 3 |
| Urology | 3 |
| Medical oncology | 3 |
| Vascular surgery | 3 |
| Neurosurgery | 3 |
| Pathology | 3 |
| Centralized Flu | 2 |
| Radiation oncology | 2 |
| Hematology/oncology | 2 |
| Micrographic Dermatologic Surgery | 2 |
| Pharmacy | 2 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 2 |
| Allergy/immunology | 2 |
| Audiologist (billing independently) | 2 |
| Interventional Cardiology | 2 |
| Critical care (intensivists) | 2 |
| Cardiac Electrophysiology | 1 |
| Rheumatology | 1 |
| Osteopathic manipulative therapy | 1 |
| Hand surgery | 1 |
| Oral surgery (dentists only) | 1 |
| Endocrinology | 1 |
| General practice | 1 |
| Geriatric medicine | 1 |
| Sleep Medicine | 1 |
| Speech / language pathology | 1 |
| Interventional radiology | 1 |
| Preventive medicine | 1 |
| Unknown physician specialty | 1 |
| Thoracic surgery | 1 |
| Psychologist (billing independently) | 1 |