| Physician assistant | 157 |
| Nurse practitioner | 156 |
| Family practice | 90 |
| Certified Registered Nurse Anesthetist (CRNA) | 63 |
| Physical therapist (private practice) | 50 |
| Internal medicine | 38 |
| Chiropractic | 35 |
| Anesthesiology | 31 |
| Emergency medicine | 30 |
| Obstetrics/gynecology | 29 |
| Mental Health Counselors | 27 |
| Mass Immunization Roster Billers | 23 |
| Licensed clinical social worker | 23 |
| Diagnostic Radiology | 23 |
| Psychiatry | 22 |
| Optometrist | 21 |
| Clinical psychologist | 19 |
| Podiatry | 17 |
| General surgery | 15 |
| Orthopedic surgery | 15 |
| Cardiology | 15 |
| Ophthalmology | 13 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 11 |
| Neurology | 11 |
| Critical care (intensivists) | 10 |
| Occupational therapist (private practice) | 9 |
| Hospitalist | 8 |
| Urology | 8 |
| Otolaryngology | 7 |
| Certified nurse midwife | 7 |
| Radiation oncology | 7 |
| Neurosurgery | 7 |
| Nephrology | 6 |
| Gastroenterology | 6 |
| Infectious disease | 6 |
| Pulmonary disease | 6 |
| Registered Dietician/Nutrition Professional | 6 |
| Dermatology | 5 |
| Sports Medicine | 5 |
| Colorectal surgery (formerly proctology) | 4 |
| Physical medicine and rehabilitation | 4 |
| Audiologist (billing independently) | 4 |
| Hematology/oncology | 4 |
| Vascular surgery | 4 |
| Plastic and reconstructive surgery | 4 |
| Interventional Cardiology | 3 |
| Hand surgery | 3 |
| Rheumatology | 3 |
| Pathology | 3 |
| Cardiac surgery | 3 |
| Geriatric medicine | 3 |
| Ambulatory Surgical Center | 3 |
| Endocrinology | 3 |
| Psychologist (billing independently) | 2 |
| Speech / language pathology | 2 |
| Cardiac Electrophysiology | 2 |
| Pediatric medicine | 2 |
| Portable X-Ray Supplier (Billing Independently) | 1 |
| Preventive medicine | 1 |
| Surgical oncology | 1 |
| Interventional Pain Management (IPM) | 1 |
| Opioid Treatment Program | 1 |
| Medical oncology | 1 |
| Hematology | 1 |
| Oral surgery (dentists only) | 1 |
| General practice | 1 |
| Clinical Laboratory (Billing Independently) | 1 |
| Thoracic surgery | 1 |
| Centralized Flu | 1 |
| Sleep Medicine | 1 |
| Medicare Diabetes Preventive Program | 1 |
| Pain Management | 1 |
| Allergy/immunology | 1 |