| Nurse practitioner | 624 |
| Physical therapist (private practice) | 400 |
| Physician assistant | 387 |
| Internal medicine | 370 |
| Licensed clinical social worker | 304 |
| Family practice | 170 |
| Anesthesiology | 156 |
| Diagnostic Radiology | 131 |
| Certified Registered Nurse Anesthetist (CRNA) | 125 |
| Obstetrics/gynecology | 121 |
| Clinical psychologist | 104 |
| Emergency medicine | 102 |
| Mental Health Counselors | 100 |
| Psychiatry | 95 |
| Optometrist | 90 |
| Ophthalmology | 85 |
| Orthopedic surgery | 76 |
| Gastroenterology | 76 |
| Mass Immunization Roster Billers | 67 |
| Chiropractic | 67 |
| Dermatology | 65 |
| Cardiology | 65 |
| Neurology | 60 |
| Audiologist (billing independently) | 56 |
| Podiatry | 56 |
| Hospitalist | 52 |
| General surgery | 50 |
| Occupational therapist (private practice) | 47 |
| Ambulatory Surgical Center | 42 |
| Otolaryngology | 39 |
| Pediatric medicine | 37 |
| Pathology | 37 |
| Physical medicine and rehabilitation | 35 |
| Hematology/oncology | 34 |
| Urology | 32 |
| Speech / language pathology | 27 |
| Rheumatology | 27 |
| Endocrinology | 26 |
| Centralized Flu | 24 |
| Registered Dietician/Nutrition Professional | 24 |
| Critical care (intensivists) | 23 |
| Allergy/immunology | 22 |
| Pulmonary disease | 16 |
| Infectious disease | 15 |
| Neurosurgery | 15 |
| Medical oncology | 14 |
| Radiation oncology | 14 |
| Clinical Laboratory (Billing Independently) | 13 |
| Nephrology | 12 |
| Pharmacy | 12 |
| Anesthesiologist Assistant | 12 |
| Plastic and reconstructive surgery | 11 |
| Interventional radiology | 11 |
| Certified nurse midwife | 9 |
| Vascular surgery | 8 |
| Geriatric medicine | 8 |
| General practice | 7 |
| Pain Management | 7 |
| Hand surgery | 6 |
| Sports Medicine | 6 |
| Maxillofacial surgery | 6 |
| Interventional Pain Management (IPM) | 5 |
| Hospice and Palliative Care | 5 |
| Oral surgery (dentists only) | 5 |
| Certified clinical nurse specialist | 5 |
| Independent Diagnostic Testing Facility (IDTF) | 4 |
| Gynecologist/oncologist | 3 |
| Colorectal surgery (formerly proctology) | 3 |
| Cardiac Electrophysiology | 3 |
| Psychologist (billing independently) | 3 |
| Interventional Cardiology | 3 |
| Surgical oncology | 3 |
| Sleep Medicine | 3 |
| Thoracic surgery | 3 |
| Nuclear medicine | 3 |
| Opioid Treatment Program | 3 |
| Marriage and Family Therapist | 3 |
| Medicare Diabetes Preventive Program | 2 |
| Preventive medicine | 2 |
| Micrographic Dermatologic Surgery | 2 |
| Portable X-Ray Supplier (Billing Independently) | 2 |
| Neuropsychiatry | 2 |
| Epileptologists | 2 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 2 |
| Cardiac surgery | 1 |
| Osteopathic manipulative therapy | 1 |
| Hematology | 1 |
| Dentist | 1 |
| Medical Genetics and Genomics | 1 |
| Addiction medicine | 1 |
| Undersea and Hyperbaric Medicine | 1 |