| Nurse practitioner | 453 |
| Internal medicine | 259 |
| Physician assistant | 245 |
| Certified Registered Nurse Anesthetist (CRNA) | 216 |
| Emergency medicine | 134 |
| Family practice | 127 |
| Physical therapist (private practice) | 111 |
| Anesthesiology | 105 |
| Obstetrics/gynecology | 89 |
| Diagnostic Radiology | 88 |
| Licensed clinical social worker | 81 |
| Psychiatry | 59 |
| Neurology | 57 |
| General surgery | 57 |
| Orthopedic surgery | 56 |
| Hospitalist | 53 |
| Pathology | 48 |
| Ophthalmology | 47 |
| Gastroenterology | 46 |
| Clinical psychologist | 44 |
| Dermatology | 44 |
| Cardiology | 42 |
| Pulmonary disease | 42 |
| Mass Immunization Roster Billers | 41 |
| Urology | 38 |
| Pediatric medicine | 35 |
| Optometrist | 35 |
| Nephrology | 35 |
| Mental Health Counselors | 31 |
| Centralized Flu | 30 |
| Otolaryngology | 28 |
| Hematology/oncology | 27 |
| Podiatry | 26 |
| Chiropractic | 26 |
| Infectious disease | 21 |
| Neurosurgery | 20 |
| Occupational therapist (private practice) | 20 |
| Rheumatology | 17 |
| Physical medicine and rehabilitation | 17 |
| Audiologist (billing independently) | 16 |
| Endocrinology | 16 |
| Interventional Cardiology | 15 |
| Vascular surgery | 14 |
| Plastic and reconstructive surgery | 13 |
| Allergy/immunology | 12 |
| Cardiac Electrophysiology | 11 |
| Pain Management | 10 |
| Pharmacy | 10 |
| Hospice and Palliative Care | 10 |
| Ambulatory Surgical Center | 10 |
| Registered Dietician/Nutrition Professional | 10 |
| Interventional radiology | 9 |
| Radiation oncology | 8 |
| General practice | 8 |
| Thoracic surgery | 8 |
| Colorectal surgery (formerly proctology) | 6 |
| Sports Medicine | 6 |
| Interventional Pain Management (IPM) | 5 |
| Speech / language pathology | 5 |
| Surgical oncology | 5 |
| Undersea and Hyperbaric Medicine | 4 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 4 |
| Certified nurse midwife | 4 |
| Independent Diagnostic Testing Facility (IDTF) | 3 |
| Geriatric medicine | 3 |
| Gynecologist/oncologist | 3 |
| Critical care (intensivists) | 3 |
| Hand surgery | 3 |
| Clinical Laboratory (Billing Independently) | 2 |
| Certified clinical nurse specialist | 2 |
| Sleep Medicine | 2 |
| Maxillofacial surgery | 2 |
| Medical oncology | 2 |
| Marriage and Family Therapist | 2 |
| Preventive medicine | 2 |
| Micrographic Dermatologic Surgery | 1 |
| Portable X-Ray Supplier (Billing Independently) | 1 |
| Epileptologists | 1 |
| Addiction medicine | 1 |
| Advanced Heart Failure and Transplant Cardiology | 1 |
| Medical Genetics and Genomics | 1 |
| Oral surgery (dentists only) | 1 |
| Opioid Treatment Program | 1 |
| Hematology | 1 |