| Nurse practitioner | 2,840 |
| Internal medicine | 1,162 |
| Family practice | 1,128 |
| Physician assistant | 1,128 |
| Certified Registered Nurse Anesthetist (CRNA) | 674 |
| Anesthesiology | 670 |
| Emergency medicine | 623 |
| Diagnostic Radiology | 517 |
| Optometrist | 510 |
| Physical therapist (private practice) | 468 |
| Obstetrics/gynecology | 452 |
| Hospitalist | 355 |
| Mass Immunization Roster Billers | 343 |
| Cardiology | 322 |
| Pathology | 295 |
| Mental Health Counselors | 283 |
| Orthopedic surgery | 281 |
| Neurology | 273 |
| Psychiatry | 268 |
| General surgery | 267 |
| Gastroenterology | 241 |
| Licensed clinical social worker | 234 |
| Chiropractic | 222 |
| Ophthalmology | 207 |
| Dermatology | 202 |
| Podiatry | 181 |
| Centralized Flu | 158 |
| Nephrology | 147 |
| Hematology/oncology | 147 |
| Clinical psychologist | 145 |
| Otolaryngology | 144 |
| Anesthesiologist Assistant | 144 |
| Pulmonary disease | 138 |
| Endocrinology | 131 |
| Urology | 125 |
| Infectious disease | 116 |
| Physical medicine and rehabilitation | 113 |
| Critical care (intensivists) | 110 |
| Pediatric medicine | 109 |
| Radiation oncology | 104 |
| Medical oncology | 103 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 99 |
| Rheumatology | 93 |
| Audiologist (billing independently) | 90 |
| Neurosurgery | 86 |
| Plastic and reconstructive surgery | 84 |
| Interventional Cardiology | 81 |
| Occupational therapist (private practice) | 80 |
| Ambulatory Surgical Center | 62 |
| Speech / language pathology | 60 |
| General practice | 55 |
| Vascular surgery | 52 |
| Thoracic surgery | 49 |
| Allergy/immunology | 48 |
| Clinical Laboratory (Billing Independently) | 45 |
| Registered Dietician/Nutrition Professional | 45 |
| Pain Management | 44 |
| Interventional radiology | 44 |
| Hospice and Palliative Care | 43 |
| Independent Diagnostic Testing Facility (IDTF) | 40 |
| Colorectal surgery (formerly proctology) | 35 |
| Geriatric medicine | 32 |
| Surgical oncology | 31 |
| Cardiac Electrophysiology | 30 |
| Sports Medicine | 27 |
| Gynecologist/oncologist | 24 |
| Pharmacy | 23 |
| Interventional Pain Management (IPM) | 21 |
| Marriage and Family Therapist | 19 |
| Hand surgery | 18 |
| Hematology | 18 |
| Certified nurse midwife | 16 |
| Nuclear medicine | 14 |
| Cardiac surgery | 12 |
| Oral surgery (dentists only) | 12 |
| Medical Genetics and Genomics | 11 |
| Advanced Heart Failure and Transplant Cardiology | 11 |
| Hematopoietic Cell Transplantation and Cellular Therapy | 10 |
| Certified clinical nurse specialist | 10 |
| Maxillofacial surgery | 9 |
| Preventive medicine | 8 |
| Sleep Medicine | 5 |
| Opioid Treatment Program | 5 |
| Epileptologists | 5 |
| Micrographic Dermatologic Surgery | 5 |
| Portable X-Ray Supplier (Billing Independently) | 4 |
| Osteopathic manipulative therapy | 4 |
| General Psychiatry | 3 |
| Psychologist (billing independently) | 2 |
| Addiction medicine | 2 |
| Home Infusion Therapy Services | 1 |
| Undersea and Hyperbaric Medicine | 1 |
| Oral and Maxillofacial Pathology | 1 |
| Single or Multispecialty Clinic or Group Practice | 1 |
| Dentist | 1 |
| Neuropsychiatry | 1 |