| Nurse practitioner | 2,115 |
| Physician assistant | 1,125 |
| Internal medicine | 994 |
| Family practice | 795 |
| Physical therapist (private practice) | 692 |
| Anesthesiology | 574 |
| Emergency medicine | 448 |
| Certified Registered Nurse Anesthetist (CRNA) | 419 |
| Optometrist | 364 |
| Diagnostic Radiology | 333 |
| Chiropractic | 306 |
| Obstetrics/gynecology | 285 |
| Mental Health Counselors | 241 |
| Mass Immunization Roster Billers | 239 |
| Orthopedic surgery | 210 |
| Psychiatry | 209 |
| Licensed clinical social worker | 202 |
| Cardiology | 195 |
| Clinical psychologist | 188 |
| General surgery | 176 |
| Gastroenterology | 170 |
| Neurology | 152 |
| Ophthalmology | 147 |
| Dermatology | 141 |
| Podiatry | 137 |
| Pediatric medicine | 133 |
| Pathology | 133 |
| Nephrology | 123 |
| Physical medicine and rehabilitation | 121 |
| Occupational therapist (private practice) | 111 |
| Hospitalist | 98 |
| Pulmonary disease | 93 |
| Otolaryngology | 90 |
| Infectious disease | 84 |
| Centralized Flu | 81 |
| Registered Dietician/Nutrition Professional | 79 |
| Audiologist (billing independently) | 77 |
| Hematology/oncology | 71 |
| Ambulatory Surgical Center | 66 |
| Urology | 65 |
| Endocrinology | 64 |
| Interventional Cardiology | 58 |
| Medical oncology | 58 |
| Rheumatology | 57 |
| Plastic and reconstructive surgery | 53 |
| Speech / language pathology | 53 |
| Neurosurgery | 47 |
| Independent Diagnostic Testing Facility (IDTF) | 47 |
| Allergy/immunology | 46 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 42 |
| Radiation oncology | 40 |
| Vascular surgery | 40 |
| Pharmacy | 40 |
| Colorectal surgery (formerly proctology) | 37 |
| Thoracic surgery | 36 |
| Critical care (intensivists) | 32 |
| Pain Management | 29 |
| Clinical Laboratory (Billing Independently) | 27 |
| Interventional Pain Management (IPM) | 25 |
| Hospice and Palliative Care | 24 |
| Surgical oncology | 22 |
| Marriage and Family Therapist | 21 |
| Interventional radiology | 21 |
| General practice | 21 |
| Geriatric medicine | 20 |
| Cardiac Electrophysiology | 20 |
| Hand surgery | 16 |
| Oral surgery (dentists only) | 12 |
| Certified nurse midwife | 11 |
| Advanced Heart Failure and Transplant Cardiology | 10 |
| Anesthesiologist Assistant | 10 |
| Sports Medicine | 8 |
| Gynecologist/oncologist | 8 |
| Certified clinical nurse specialist | 6 |
| Portable X-Ray Supplier (Billing Independently) | 6 |
| Maxillofacial surgery | 6 |
| Opioid Treatment Program | 5 |
| Nuclear medicine | 5 |
| Osteopathic manipulative therapy | 5 |
| Sleep Medicine | 5 |
| Hematology | 4 |
| Hematopoietic Cell Transplantation and Cellular Therapy | 3 |
| Cardiac surgery | 3 |
| Dentist | 3 |
| Micrographic Dermatologic Surgery | 3 |
| Psychologist (billing independently) | 2 |
| Single or Multispecialty Clinic or Group Practice | 2 |
| General Psychiatry | 2 |
| Oral and Maxillofacial Pathology | 1 |
| Home Infusion Therapy Services | 1 |
| Addiction medicine | 1 |
| Preventive medicine | 1 |