| Nurse practitioner | 477 |
| Certified Registered Nurse Anesthetist (CRNA) | 192 |
| Physician assistant | 189 |
| Physical therapist (private practice) | 168 |
| Family practice | 160 |
| Emergency medicine | 96 |
| Internal medicine | 93 |
| Obstetrics/gynecology | 74 |
| Anesthesiology | 72 |
| Hospitalist | 70 |
| Psychiatry | 63 |
| Licensed clinical social worker | 52 |
| Mass Immunization Roster Billers | 51 |
| Chiropractic | 50 |
| Diagnostic Radiology | 47 |
| Mental Health Counselors | 47 |
| Optometrist | 43 |
| General surgery | 36 |
| Occupational therapist (private practice) | 34 |
| Ophthalmology | 32 |
| Orthopedic surgery | 30 |
| Cardiology | 28 |
| Pulmonary disease | 25 |
| Centralized Flu | 21 |
| Gastroenterology | 21 |
| Nephrology | 21 |
| Dermatology | 20 |
| Neurology | 20 |
| Otolaryngology | 18 |
| Podiatry | 17 |
| Clinical psychologist | 17 |
| Speech / language pathology | 16 |
| Interventional Cardiology | 15 |
| Pathology | 15 |
| Hematology/oncology | 15 |
| Audiologist (billing independently) | 14 |
| Urology | 14 |
| Neurosurgery | 13 |
| Infectious disease | 12 |
| Plastic and reconstructive surgery | 11 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 11 |
| Ambulatory Surgical Center | 11 |
| Independent Diagnostic Testing Facility (IDTF) | 11 |
| Physical medicine and rehabilitation | 10 |
| Critical care (intensivists) | 10 |
| Rheumatology | 10 |
| Cardiac Electrophysiology | 10 |
| Pediatric medicine | 8 |
| Pharmacy | 6 |
| Vascular surgery | 6 |
| Radiation oncology | 6 |
| Interventional radiology | 6 |
| Endocrinology | 5 |
| Colorectal surgery (formerly proctology) | 5 |
| Thoracic surgery | 5 |
| Sports Medicine | 5 |
| Registered Dietician/Nutrition Professional | 4 |
| Allergy/immunology | 4 |
| Certified nurse midwife | 4 |
| Hand surgery | 4 |
| Maxillofacial surgery | 4 |
| Geriatric medicine | 4 |
| Neuropsychiatry | 3 |
| General practice | 3 |
| Hospice and Palliative Care | 3 |
| Cardiac surgery | 3 |
| Surgical oncology | 3 |
| Interventional Pain Management (IPM) | 2 |
| Preventive medicine | 2 |
| Advanced Heart Failure and Transplant Cardiology | 2 |
| Clinical Laboratory (Billing Independently) | 2 |
| Pain Management | 2 |
| Gynecologist/oncologist | 2 |
| Certified clinical nurse specialist | 2 |
| Medical Genetics and Genomics | 1 |
| Public Health or Welfare Agencies (Federal, State, and local) | 1 |
| Undersea and Hyperbaric Medicine | 1 |
| Sleep Medicine | 1 |
| Nuclear medicine | 1 |
| Marriage and Family Therapist | 1 |
| Single or Multispecialty Clinic or Group Practice | 1 |
| Opioid Treatment Program | 1 |
| General Psychiatry | 1 |