| Nurse practitioner | 1,214 |
| Physician assistant | 975 |
| Internal medicine | 562 |
| Physical therapist (private practice) | 354 |
| Family practice | 297 |
| Licensed clinical social worker | 215 |
| Anesthesiology | 194 |
| Emergency medicine | 188 |
| Diagnostic Radiology | 158 |
| Obstetrics/gynecology | 158 |
| Hospitalist | 143 |
| Certified Registered Nurse Anesthetist (CRNA) | 129 |
| Chiropractic | 126 |
| Neurology | 118 |
| Psychiatry | 116 |
| Optometrist | 111 |
| Mass Immunization Roster Billers | 93 |
| Ophthalmology | 83 |
| Orthopedic surgery | 82 |
| Cardiology | 78 |
| Pathology | 76 |
| Clinical psychologist | 63 |
| General surgery | 60 |
| Dermatology | 51 |
| Gastroenterology | 47 |
| Mental Health Counselors | 47 |
| Pulmonary disease | 46 |
| Podiatry | 42 |
| Certified nurse midwife | 38 |
| Nephrology | 37 |
| Urology | 37 |
| Otolaryngology | 36 |
| Physical medicine and rehabilitation | 36 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 35 |
| Hematology/oncology | 35 |
| Occupational therapist (private practice) | 33 |
| Pediatric medicine | 32 |
| Infectious disease | 31 |
| Centralized Flu | 27 |
| Audiologist (billing independently) | 24 |
| Endocrinology | 24 |
| Neurosurgery | 23 |
| Speech / language pathology | 23 |
| Geriatric medicine | 22 |
| Radiation oncology | 21 |
| Hospice and Palliative Care | 18 |
| Vascular surgery | 16 |
| Colorectal surgery (formerly proctology) | 16 |
| Allergy/immunology | 15 |
| Plastic and reconstructive surgery | 15 |
| Thoracic surgery | 14 |
| Medical oncology | 14 |
| Pharmacy | 14 |
| Rheumatology | 14 |
| Critical care (intensivists) | 11 |
| Hematology | 11 |
| Interventional Cardiology | 10 |
| Registered Dietician/Nutrition Professional | 9 |
| Oral surgery (dentists only) | 8 |
| Hematopoietic Cell Transplantation and Cellular Therapy | 7 |
| Interventional radiology | 7 |
| Pain Management | 7 |
| Cardiac Electrophysiology | 7 |
| Surgical oncology | 6 |
| Ambulatory Surgical Center | 6 |
| Hand surgery | 6 |
| Sports Medicine | 4 |
| Dentist | 3 |
| Marriage and Family Therapist | 3 |
| Interventional Pain Management (IPM) | 3 |
| Cardiac surgery | 3 |
| Osteopathic manipulative therapy | 3 |
| Gynecologist/oncologist | 3 |
| General practice | 3 |
| Sleep Medicine | 3 |
| Maxillofacial surgery | 2 |
| Neuropsychiatry | 2 |
| Preventive medicine | 2 |
| Portable X-Ray Supplier (Billing Independently) | 2 |
| Advanced Heart Failure and Transplant Cardiology | 2 |
| General Psychiatry | 2 |
| Independent Diagnostic Testing Facility (IDTF) | 2 |
| Nuclear medicine | 1 |
| Clinical Laboratory (Billing Independently) | 1 |
| Medical Toxicology | 1 |
| Micrographic Dermatologic Surgery | 1 |
| Psychologist (billing independently) | 1 |
| Epileptologists | 1 |
| Opioid Treatment Program | 1 |