| Nurse practitioner | 736 |
| Physician assistant | 532 |
| Family practice | 230 |
| Physical therapist (private practice) | 221 |
| Licensed clinical social worker | 158 |
| Internal medicine | 153 |
| Certified Registered Nurse Anesthetist (CRNA) | 136 |
| Anesthesiology | 107 |
| Emergency medicine | 94 |
| Diagnostic Radiology | 90 |
| Psychiatry | 72 |
| Clinical psychologist | 71 |
| Mass Immunization Roster Billers | 68 |
| Chiropractic | 67 |
| Hospitalist | 67 |
| Obstetrics/gynecology | 67 |
| Mental Health Counselors | 59 |
| Orthopedic surgery | 57 |
| Cardiology | 54 |
| Optometrist | 53 |
| Neurology | 44 |
| Ophthalmology | 39 |
| General surgery | 39 |
| Pathology | 37 |
| Gastroenterology | 34 |
| Podiatry | 32 |
| Urology | 32 |
| Hematology/oncology | 30 |
| Occupational therapist (private practice) | 29 |
| Otolaryngology | 29 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 27 |
| Pulmonary disease | 25 |
| Physical medicine and rehabilitation | 21 |
| Centralized Flu | 20 |
| Nephrology | 19 |
| Endocrinology | 17 |
| Registered Dietician/Nutrition Professional | 17 |
| Radiation oncology | 17 |
| Dermatology | 16 |
| Audiologist (billing independently) | 15 |
| Critical care (intensivists) | 13 |
| Neurosurgery | 13 |
| Certified nurse midwife | 13 |
| Plastic and reconstructive surgery | 12 |
| Ambulatory Surgical Center | 12 |
| Infectious disease | 12 |
| Rheumatology | 12 |
| Colorectal surgery (formerly proctology) | 12 |
| Speech / language pathology | 11 |
| Geriatric medicine | 11 |
| Vascular surgery | 10 |
| Pain Management | 10 |
| Marriage and Family Therapist | 10 |
| Cardiac surgery | 9 |
| Surgical oncology | 7 |
| Interventional radiology | 7 |
| Thoracic surgery | 7 |
| Cardiac Electrophysiology | 6 |
| Allergy/immunology | 5 |
| Pharmacy | 5 |
| Hand surgery | 5 |
| Pediatric medicine | 5 |
| Hospice and Palliative Care | 4 |
| Undersea and Hyperbaric Medicine | 4 |
| Nuclear medicine | 3 |
| Medical oncology | 3 |
| Opioid Treatment Program | 3 |
| General practice | 2 |
| Independent Diagnostic Testing Facility (IDTF) | 2 |
| Sports Medicine | 2 |
| Interventional Cardiology | 2 |
| Clinical Laboratory (Billing Independently) | 2 |
| Oral surgery (dentists only) | 2 |
| Neuropsychiatry | 1 |
| Certified clinical nurse specialist | 1 |
| Dentist | 1 |
| Micrographic Dermatologic Surgery | 1 |
| Hematology | 1 |
| Prosthodontics | 1 |
| Portable X-Ray Supplier (Billing Independently) | 1 |