| Physician assistant | 40 |
| Nurse practitioner | 37 |
| Physical therapist (private practice) | 34 |
| Family practice | 17 |
| Licensed clinical social worker | 16 |
| Anesthesiology | 13 |
| Internal medicine | 12 |
| Chiropractic | 11 |
| Orthopedic surgery | 11 |
| Obstetrics/gynecology | 10 |
| Optometrist | 9 |
| Emergency medicine | 8 |
| Clinical psychologist | 7 |
| Dermatology | 6 |
| Podiatry | 6 |
| Hospitalist | 6 |
| Mass Immunization Roster Billers | 6 |
| Ambulatory Surgical Center | 5 |
| Diagnostic Radiology | 5 |
| Mental Health Counselors | 5 |
| Ophthalmology | 5 |
| Certified Registered Nurse Anesthetist (CRNA) | 5 |
| Otolaryngology | 4 |
| Occupational therapist (private practice) | 4 |
| General surgery | 3 |
| Gastroenterology | 3 |
| Audiologist (billing independently) | 3 |
| Certified nurse midwife | 3 |
| Pediatric medicine | 3 |
| Cardiology | 2 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 2 |
| Physical medicine and rehabilitation | 2 |
| Speech / language pathology | 2 |
| Registered Dietician/Nutrition Professional | 2 |
| Urology | 2 |
| Psychiatry | 2 |
| General practice | 1 |
| Pharmacy | 1 |
| Medical oncology | 1 |
| Infectious disease | 1 |
| Gynecologist/oncologist | 1 |
| Plastic and reconstructive surgery | 1 |
| Sleep Medicine | 1 |
| Marriage and Family Therapist | 1 |
| Rheumatology | 1 |
| Hematology/oncology | 1 |
| Interventional Pain Management (IPM) | 1 |
| Opioid Treatment Program | 1 |
| Allergy/immunology | 1 |
| Pathology | 1 |
| Sports Medicine | 1 |
| Undersea and Hyperbaric Medicine | 1 |
| Interventional Cardiology | 1 |
| Oral surgery (dentists only) | 1 |
| Dentist | 1 |
| Public Health or Welfare Agencies (Federal, State, and local) | 1 |
| Pulmonary disease | 1 |