Healthcare Insights

A comprehensive list of medical specialties and subspecialties

Medical specialties are classifications for providers based on professional medical board certifications. Board-certified specialties enable physicians to articulate their expertise and professionalism while making it easier for healthcare organizations to target staffing prospects—and giving consumers and patients insight into the competence of the person responsible for their treatment.

However, board certification doesn’t always entirely capture the scope of a provider’s practice. Plus, self-reported specialty information can be unreliable or become outdated. That’s why the Definitive Healthcare platform delivers both self-reported specialty information along with a proprietary claims-based model that uses artificial intelligence, procedure claims, and distinct reference and affiliation data points to accurately determine specialties.

Definitive Healthcare tracks 46 distinct specialty categories and 128 subspecialty categories within our platform. Below, we’ve compiled lists of medical specialties and subspecialties using our proprietary claims-based model to demonstrate the breadth of expertise across the healthcare landscape.

Top 20 medical specialties by provider count

RankSpecialty% of providers in U.S.Explore dataset
1Nursing13.56%Explore
2Therapy/Rehab11.15%Explore
3Primary Care8.74%Explore
4Social Work8.45%Explore
5Other8.16%Explore
6Physician Assistant6.18%Explore
7Dentistry5.85%Explore
8Anesthesiology4.58%Explore
9Surgery3.26%Explore
10Urgent/Emergency Care2.94%Explore
11Optometry/Ophthalmology2.80%Explore
12Psychology2.62%Explore
13Pediatric Medicine2.37%Explore
14Psychiatry2.12%Explore
15Obstetrics/Gynecology1.89%Explore
16Hospital Medicine1.70%Explore
17Radiology1.60%Explore
18Cardiology1.43%Explore
19Hematology/Oncology1.02%Explore
20Neurology0.86%Explore

Fig. 1 – Analysis of primary medical specialties from Definitive Healthcare’s PhysicianView product. Data sourced from NPI Registry and Physician Compare for May 2023. Provider count derived using claims-based specialty model.

What are the top medical specialties?

Nursing is the top medical specialty, representing 13.56% of all healthcare professionals tracked in our database. In second place is therapy/rehab, accounting for 11.15% of all healthcare professionals. Primary care is the third most common specialty, with 8.74% of the total provider workforce.

Top 20 medical subspecialties by provider count

RankSubspecialty% of providers in U.S.Explore dataset
1Nurse Practitioner13.05%Explore
2Social Work8.45%Explore
3Other8.16%Explore
4Physician Assistant6.18%Explore
5Physical Therapy5.98%Explore
6Dentistry5.77%Explore
7Family Practice4.46%Explore
8Internal Medicine3.91%Explore
9Emergency Medicine2.70%Explore
10Clinical Psychology2.59%Explore
11Certified Registered Nurse Anesthetist2.41%Explore
12Pediatric Medicine2.37%Explore
13Chiropractic2.29%Explore
14Psychiatry2.09%Explore
15Anesthesiology1.97%Explore
16Optometry1.96%Explore
17Obstetrics/Gynecology1.88%Explore
18Hospital Medicine1.70%Explore
19Diagnostic Radiology1.58%Explore
20Cardiology1.18%Explore

Fig. 2 Analysis of medical subspecialties from Definitive Healthcare’s PhysicianView product. Data sourced from NPI Registry and Physician Compare for May 2023. Provider count derived using claims-based specialty model.

What are the top medical subspecialties?

Nurse practitioner is the most prevalent medical subspecialty, representing 13.05% of all healthcare professionals within our database. Nurse practitioners are nurses who leverage advanced clinical education to perform many of the same duties as physicians.

Social work comes in second place on our list with 8.45% of total healthcare professionals. Social workers help individuals and families navigate and treat mental, behavioral, and emotional problems, usually through therapy or counseling.

In third place is the “other” category, accounting for 8.16% of all healthcare professionals. Those in this category represent a wide array of behavioral, psychological, and medical professionals whose work doesn’t necessarily fit neatly into other provider specialties and subspecialties.

How are medical specialties and subspecialties structured?

In the Definitive Healthcare PhysicianView product, subspecialties are categorized within specialties based on their function. Subspecialties matching their parent specialty name are excluded here.

  • Addiction Medicine
  • Adolescent Medicine
  • Adult Medicine
  • Aerospace Medicine
  • Allergy/Immunology/Rheumatology
    • Allergy/Immunology
    • Pediatric Allergy/Immunology
    • Pediatric Rheumatology
    • Rheumatology
  • Anesthesiology
    • Anesthesiology Assistant
    • Certified Registered Nurse Anesthetist
    • Pediatric Anesthesiology
  • Audiology
  • Cardiology
    • Cardiac Electrophysiology
    • Cardiac Surgery
    • Interventional Cardiology
    • Pediatric Cardiology
    • Peripheral Vascular Disease
  • Critical Care
    • Neonatal-Perinatal Medicine
    • Pediatric Critical Care
  • Dentistry
    • Oral and Maxillofacial Surgery
    • Pediatric Dentistry
  • Dermatology
  • Developmental and Behavioral Medicine
    • Pediatric Developmental and Behavioral Medicine
  • Diet/Nutrition
  • Endocrinology
    • Pediatric Endocrinology
    • Reproductive Endocrinology
  • Gastroenterology
    • Pediatric Gastroenterology
  • Geriatric Medicine
  • Hematology/Oncology
    • Gynecological Oncology
    • Hematology
    • Medical Oncology
    • Oncology
    • Pediatric Oncology
    • Radiation Oncology
  • Home Health
    • Home Health Aide
  • Hospice and Palliative Care
  • Hospital Medicine
  • Infectious Disease
    • Pediatric Infectious Disease
  • Men’s Health
  • Nephrology
    • Pediatric Nephrology
  • Neurology
    • Electrodiagnostic Medicine
    • Pediatric Neurology
  • Nursing
    • Certified Clinical Nurse Specialist
    • Certified Nurse Midwife
    • Nurse Practitioner
  • Obstetrics/Gynecology
    • Maternal and Fetal Medicine
  • Optometry/Ophthalmology
    • Ophthalmology
    • Optometry
  • Otolaryngology
    • Facial Plastic Surgery
    • Pediatric Otolaryngology
  • Pain Management
    • Interventional Pain Management
  • Pathology
    • Clinical Pathology
    • Cytopathology
    • Forensic Pathology
    • Pediatric Pathology
  • Pediatric Medicine
  • Physician Assistant
  • Podiatry
  • Primary Care
    • Family Practice
    • General Practice
    • Internal Medicine
    • Preventive Medicine
  • Psychiatry
    • Addiction Psychiatry
    • Forensic Psychiatry
    • Geriatric Psychiatry
    • Neuropsychiatry
    • Pediatric Psychiatry
    • Psychosomatic Medicine
  • Psychology
    • Clinical Psychology
    • Clinical Neuropsychology
  • Pulmonology
    • Pediatric Pulmonology
  • Radiology
    • Diagnostic Radiology 
    • Interventional Radiology
    • Neuroradiology
    • Nuclear Medicine
    • Pediatric Radiology
  • Sleep Medicine
  • Social Work
  • Surgery
    • Colorectal Surgery
    • Foot and Ankle Surgery
    • General Surgery
    • Hand Surgery
    • Head and Neck Surgery
    • Neurosurgery
    • Orthopedic Surgery
    • Orthopedic Spine Surgery
    • Pediatric Surgery
    • Pediatric Orthopedic Surgery
    • Plastic and Reconstructive Surgery
    • Surgical Oncology
    • Thoracic Surgery
    • Trauma Surgery
    • Vascular Surgery
  • Therapy/Rehab
    • Chiropractic
    • Massage Therapy
    • Occupational Therapy
    • Osteopathic Manipulative Medicine
    • Pediatric Physical Therapy
    • Pediatric Rehabilitation Medicine
    • Physical Medicine and Rehabilitation
    • Physical Therapy
    • Speech Language Pathology
    • Sports Medicine
  • Urgent/Emergency Care
    • Emergency Medicine
    • Pediatric Emergency Medicine
  • Urology
    • Pediatric Urology
  • Women’s Health

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