| Nurse practitioner | 448 |
| Licensed clinical social worker | 207 |
| Physician assistant | 181 |
| Physical therapist (private practice) | 133 |
| Mental Health Counselors | 132 |
| Internal medicine | 115 |
| Family practice | 78 |
| Emergency medicine | 70 |
| Certified Registered Nurse Anesthetist (CRNA) | 64 |
| Optometrist | 62 |
| Anesthesiology | 61 |
| Chiropractic | 55 |
| Clinical psychologist | 53 |
| Hospitalist | 48 |
| Psychiatry | 44 |
| Diagnostic Radiology | 43 |
| Obstetrics/gynecology | 41 |
| Mass Immunization Roster Billers | 34 |
| Cardiology | 34 |
| General surgery | 31 |
| Orthopedic surgery | 29 |
| Pediatric medicine | 28 |
| Gastroenterology | 27 |
| Pulmonary disease | 26 |
| Neurology | 25 |
| Ophthalmology | 22 |
| Occupational therapist (private practice) | 20 |
| Pathology | 18 |
| Podiatry | 17 |
| Centralized Flu | 16 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 15 |
| Hematology/oncology | 13 |
| Audiologist (billing independently) | 13 |
| Otolaryngology | 13 |
| Dermatology | 12 |
| Certified nurse midwife | 11 |
| Neurosurgery | 10 |
| Radiation oncology | 10 |
| Urology | 10 |
| Certified clinical nurse specialist | 9 |
| Registered Dietician/Nutrition Professional | 9 |
| Rheumatology | 9 |
| Speech / language pathology | 7 |
| Nephrology | 7 |
| Endocrinology | 7 |
| Vascular surgery | 6 |
| Physical medicine and rehabilitation | 6 |
| Oral surgery (dentists only) | 6 |
| Pharmacy | 6 |
| Infectious disease | 6 |
| Thoracic surgery | 5 |
| Cardiac Electrophysiology | 5 |
| Plastic and reconstructive surgery | 5 |
| Pain Management | 4 |
| Critical care (intensivists) | 4 |
| Clinical Laboratory (Billing Independently) | 4 |
| General practice | 4 |
| Marriage and Family Therapist | 4 |
| Medical oncology | 4 |
| Interventional Cardiology | 4 |
| Allergy/immunology | 4 |
| Hand surgery | 4 |
| Ambulatory Surgical Center | 3 |
| Sleep Medicine | 2 |
| Interventional radiology | 2 |
| Independent Diagnostic Testing Facility (IDTF) | 2 |
| Surgical oncology | 2 |
| Addiction medicine | 2 |
| Dentist | 2 |
| Cardiac surgery | 2 |
| Gynecologist/oncologist | 2 |
| Hospice and Palliative Care | 2 |
| Micrographic Dermatologic Surgery | 1 |
| Home Infusion Therapy Services | 1 |
| Sports Medicine | 1 |
| Public Health or Welfare Agencies (Federal, State, and local) | 1 |
| Anesthesiologist Assistant | 1 |
| Opioid Treatment Program | 1 |
| Hematology | 1 |