Different Types of Doctors: What They Do, Medical Doctors & Physicians Salary

Different Types of Doctors: What They Do, Medical Doctors & Physicians Salary

A note from the author, Paweł Dąbrowski, PhD, education expert with 10+ years of experience. He publishes his work in many prestigious media outlets and academic publications focused on education:

Modern medicine has certainly come a long way from the age of apothecaries and herbalists. With the available medical technologies and techniques, doctors are able to effectively save lives as well as help patients be at their healthiest. Plus, with neurosurgeons yielding up to $814,801 in annual salaries (Salary.com, 2022), it is no longer surprising that being a medical doctor is among the most sought-after professionals globally. 

Indeed, medical doctors have certainly come a long way since the same shamans, priests or priestesses, and other religious vessels were considered as divinely appointed healers, mediating between stricken men and their deities. After all, diseases and illnesses were once thought to be punishments from the gods or supernatural beings who might have been inadvertently offended by humans in one way or another (Early concepts of disease, n.d.).

Thankfully for us, we now think of going to our doctors instead of exotic healers when we feel unwell. Usually, we go to a general doctor first before we are referred to a specialist in case we need to see one. As it is, there are multiple types of doctors ready to attend to patients with specific diseases or illnesses. If you’re interested in learning more about the different types of doctors available, you can refer to this types of doctors list.

Types of Doctors

  1. What are the types of doctors?
  2. D.O. vs M.D.: 3 Key Differences
  3. Key Statistics on Types of Doctors
  4. What are the requirements to study medicine?
  5. How much does it cost to study medicine?
  6. The Best Schools to Study Medicine
  7. How long does it take to become a licensed doctor?
  8. How much do doctors earn?
  9. Famous People Who Studied Medicine

Across the globe, there is an uneven distribution of health workers. For every 10,000 members of the population, there are only 10 or less than 10 physicians available to cater to them in 40% of World Health Organization member states.

Meanwhile in the United States, Kerns and Willis (2020) state that the country's problem in the healthcare system is not the shortage of doctors alone. Rather, there are other contributing factors:

  • Uneven distribution of primary care physicians
  • Incomplete insurance coverage
  • Inconvenient duty hours
  • Inflexible care models
  • Aversion to public health programs like Medicare
  • Inefficient use of physician labor

Moreover, most of the specialists in the U.S. are concentrated in states like California, and New York. Because of this, people sometimes have to travel long distances to get the care they need, especially when they are looking for a unique specialist and certain types of physicians.


What are the types of doctors?

Some of the most common physicians that patients are more familiar with are family physicians, internal medicine doctors, pediatricians, obstetricians/gynecologists, and surgeons (Santiago, 2020; WebMD, 2018). Each of these different types of doctors specializes in specific parts of the anatomy or body systems. So, what types of doctors are there? Here are the most common ones.

  • Family Physician - Provides basic health care to patients of all ages. They are usually the ones to identify illnesses that may require special attention.
  • Pediatrician -  They take care of young patients, usually babies, toddlers, and young children up to age eighteen or twenty-one. Though people are generally considered adults when they reach the age of 18, pediatricians can still cover young adults up to age 21, as it is still considered to be in the late adolescent stage of growth and development (Peykoff Hardin, A., Hackell, J.M., & Committee on Practice and Ambulatory Medicine, 2017).
  • Internal Medicine Physician - They are trained to prevent, diagnose, and treat diseases and illnesses that affect adults. They are also called general internists, who cover a broad array of illnesses.
  • Obstetrician/Gynecologist - Doctors who are concerned with the reproductive health of females. They take care of patients who have hormone problems or are undergoing menopause. They are better known for assisting pregnant women and delivering babies.
  • Psychiatrist - This specialist focuses on mental and emotional disorders, helping people cope with their personal issues.
  • Dermatologist - This is the doctor to whom people go to for their skin problems. They are best known for administering Botox and executing cosmetic surgery and reconstructive surgery.
  • Pulmonologist - People go to this specialist when they have ailments like pneumonia, emphysema, asthma, and lung cancer. They can also visit a pulmonologist if they have sleep problems due to breathing troubles.
  • Neurologist - This is a doctor who is concerned with conditions that involve the brain, nerves, or spine.
  • Oncologist - This type of physician practices a sub-specialty related to surgical, medical, or radiation oncology. They attend to cancer patients by administering treatments for cancer or for symptoms caused by it.
  • Anesthesiologist - Rather than catering to patients directly, anesthesiologists work with other doctors during surgery. They are responsible for developing anesthetic plans and the administration of anesthetics for the duration of surgeries.
  • Radiologist - A physician which pursued a radiology career is mainly responsible for conducting and interpreting diagnostic tests such as X-rays.
  • Ophthalmologist – This specialist is the one people go to when they have problems with their eyesight. They help patients care for their eyes by providing treatments and prescribing glasses and contact lenses. On top of it all, they perform surgery when necessary.
  • Gastroenterologist – This type of physician is concerned with a patient’s digestive system. If people have a problem with bowel movements, abdominal pain, and rectal bleeding, then they go to see a gastroenterologist.
  • Otolaryngologist – Otherwise known as ear, nose, and throat physicians, otolaryngologists help people with hearing problems, nasal congestion, ear infections, and problems with their neck.

The above-mentioned are only M.D.s or medical doctors, though. There is actually another kind of doctor, which is a D.O. They are doctors of osteopathic medicine who treat patients holistically rather than treating targeted areas of systems of the body (Piedmont Healthcare, 2020).

D.O. vs M.D.: 3 Key Differences

When people visit the hospital or a clinic, they are more likely to encounter physicians who have M.D. at the end of their names. However, there is a D.O. too, which means doctor of osteopathic medicine. But exactly what is a D.O. doctor? And how do they differ from M.D.s?

Patient Care

To understand what doctors of osteopathic medicine or D.O.s do, it is necessary to understand what osteopathy means. It is similar to the medicine that most people are familiar with, as it involves prescription drugs, surgery, and equipment and technology for diagnosing and treating illnesses and injuries. However, what distinguishes osteopathic medicine is its approach to health and wellness: it is more concerned with whole-body wellness and disease and injury prevention (American Osteopathic Association, n.d.; Fletcher, 2020).

Thus, doctors of osteopathic medicine examine the patient as a whole. This means that they take the symptoms of illness or disease into consideration rather than focusing on them only (Bauer, 2019).

On the other hand, medical doctors or M.D.s have an allopathic approach to healthcare. This is the conventional and mainstream medicine that most people know. This means that physicians treat diseases, illnesses, and their symptoms in a targeted manner.

Education and Training

D.O.s also undertake rigorous training. They have to go through four years of study in an osteopathic medical school where they receive skills and knowledge in preventative and comprehensive medicine. On top of that, they have thorough training in the musculoskeletal system, as covered by physiology and kinesiology (Doctors That DO, 2015).

After graduating, they also need to apply as interns, residents, or fellows in medical institutions. In this part of the process, they are expected to work closely with other professionals in the field ranging from fellow residents, nurses, and gerontologists. Only then are they able to apply for a license and a board certification (Doctors That DO, 2015).

M.D.s are also the same; they go to a medical school and they sign on as residents, fellows, or interns in hospitals. Once they have completed their training, they can apply for a medical license.


During their residency years, medical and osteopathic doctors alike undergo specialization training. According to the American Medical Association (2018), 32% of M.D.s went into primary care. The breakdown is as follows:

  • 12.7% general practice
  • 12.9% internal medicine
  • 6.5% pediatric medicine

Meanwhile, 57% of D.O.s chose primary care in the same year, of which:

  • 31.9% chose family medicine
  • 17.8% internal medicine
  • 6.8% pediatric medicine

Overall, only 7.8% of physicians of the 892,752 active physicians in the United States in 2017 have D.O. degrees. The most number of active physicians with D.O. degrees are in the field of family medicine or general practice (18,762). The specialty is followed by internal medicine (6,386), emergency medicine (4,789), anesthesiology (2,752), and obstetrics and gynecology (2,813) (Association of American Medical Colleges, 2018).

Source: Association of American Medical Colleges

Key Statistics of Types of Doctors 

Selecting a medical field is crucial for every student who is aiming to become a physician. Students, however, make their choice depending on their personal preference or experience or they can be practical about it by looking at doctors salary and perks. But selecting among different kinds of doctors can be quite difficult. Here are some statistics across various types of medical doctors that can give you a general idea of key considerations in choosing your field or specialization.

  • There were a total of 4,946 programs for specialty matching in 2019-2020 (National Resident Matching Program, 2020).
  • Internal Medicine had the most programs, 1,872 (NRMP, 2020).
  • For those, there were 11,545 open positions (NRMP, 2020).
  • 50.1% were filled by U.S. medical graduates (NRMP, 2020).
  • At the end of the matching period, 1,149 programs were left unfilled (NRMP, 2020).
  • 103 U.S. medical school graduates were interested in at least one allergy and immunology program (NRMP, 2020).
  • However, there were 142 positions for 85 allergy and immunology programs (NRMP, 2020).
  • Only 135 positions in those programs were filled (NRMP, 2020).
  • Demand for physicians increased by 5% in the top 10 metropolitan areas (Doximity, 2019).
  • New Orleans, Louisiana, has the highest pay growth percentage at 10% (Doximity, 2019).
  • Milwaukee, Wisconsin, is the most generous towards physicians, as the average compensation is $395,363 per year (Doximity, 2019).
  • Neurosurgeons are the highest-paid doctors, as they take home an average of $616,823 per year (Doximity, 2019).
  • The most stressful area of medicine is critical care, with 48% of doctors suffering from burnout (Berg, 2018).
  • 48% of neurologists get burnout, too (Berg, 2018).
  • 15% of physicians admitted to having clinical or colloquial depression (Berg, 2018).

What are the requirements to study medicine?

The prerequisites for studying medicine are rigorous to ensure the quality of graduates. Requirements of each school may differ but there is one common qualification: a four-year undergraduate degree related to medicine. Those interested in becoming medical practitioners must also demonstrate their knowledge in biology, general chemistry, and organic chemistry. They can do this through the Medical College Admission Test (MCAT) (The Medic Portal, 2019).

The MCAT is a standardized test and is computer-based. This has been a part of the admission process of medical schools for all types of doctors in the U.S. for over 90 years. Some medical colleges in Canada also require MCAT scores. Additionally, exam takers can expect to face questions regarding biochemistry as well as the psychological, biological, and social foundations of behavior. Every year, around 85,000 individuals take the test (Association of American Medical Colleges, 2015).

To give students an idea of the test scores that they should aim for, Kowarski (2020) reports that the median undergraduate GPA of first-year students during the fall 2019 admission at ranked medical schools was 3.75. And for MCAT, the median score was 512, which is 16 points shy of the maximum score.

Moreover, medical schools expect applicants to have a GPA of 3.3 in their undergraduate degree. On top of that, they scrutinize the scores or grades of students in science-related courses (Kowarski, 2020).

Residency and Specialization

After four years in medical school, students need to undergo a minimum of three years' residency training. This is an important step as without it, they are unable to acquire a professional license to practice medicine (Study.com, 2020). Additionally, the length of training varies depending on the specialty that students want to focus on. For example, those who want to go on to neurosurgery need to spend seven years in a residency program while those who wish to focus on pediatrics are only required to have three years' training (Washington University School of Medicine in St. Louis, n.d.).

There are numerous residency and fellowship programs across the United States, many of which are also open to international applicants. Indeed, of the 11,545 positions opened during the 2019-2020 application period, only 50.1% were U.S. medical school graduates (NRMP, 2020).

How much does it cost to study medicine?

According to AAMC (2019), the average cost of studying medicine in 2019-2020 for residents, inclusive of tuition, additional fees, and health insurance was $37,556 in public schools. Meanwhile, residents who opted to matriculate in private schools faced an average cost of $60,665.

Those who studied in an out-of-state public school had to spend an average of $61,858. If they opted for an out-of-state private school for medicine, they had to handle an average cost of $62,230 (AAMC, 2019).

Among the 48 ranked private medical educational institutions, the annual average cost of medicine for 2019-2020 was $57,937. The cost of the most expensive private school, Columbia University, was significantly higher: $68,885 (Kowarski, 2020).

According to the university statistics for 2021, the world-renowned Johns Hopkins School of Medicine posted that the tuition for the school year 2020-2021 is $56,500 for a year alone. Apart from that, there are other fees such as health insurance premium, university health service fee, dental insurance, matriculation fee (first year only), and imaging fee. Of course, there are indirect costs as well that include books and supplies, board and lodging, travel expenses, personal expenses, United States Medical Licensing Examination (USMLE), and USMLE Travel (Strickland, 2020).

Source: Association of American Medical Colleges, 2020


The Best Schools to Study Medicine

Physicians who want to be at the top of their fields also aim to study at the best medical schools. According to U.S. News, the best institutions in the U.S. are spearheaded by Harvard University. Johns Hopkins University follows it. In the list, too, is the Mayo Clinic School of Medicine in Alix, and medical schools in two campuses of the University of California.

  1. Harvard Medical School
  2. Johns Hopkins University
  3. University of Pennsylvania Perelman School of Medicine
  4. New York University Grossman School of Medicine
  5. Stanford Medicine
  6. Columbia University Vagelos College of Physicians and Surgeons
  7. Mayo Clinic Alix School of Medicine
  8. David Geffen School of Medicine at UCLA
  9. UCSF School of Medicine
  10. Washington University School of Medicine in St. Louis

On the global stage, the Harvard Medical School still tops the list. The University of Oxford follows suit, with the University of Cambridge right behind. Other U.S. schools are in the top 10 list, too, which is partly dominated by schools in the United Kingdom. One school from Sweden, Karolinksa Institutet, made the list at the fifth place, which it shares with Johns Hopkins University (Lane, 2020).

  1. Harvard Medical School
  2. University of Oxford Medical Sciences Division
  3. University of Cambridge School of Clinical Medicine
  4. Stanford Medicine
  5. Johns Hopkins University
  6. Karolinksa Institutet (shares fifth place with Johns Hopkins University)
  7. David Geffen School of Medicine at UCLA
  8. University College London Medical School
  9. Yale School of Medicine
  10. Imperial College London Faculty of Medicine
  11. UCSF School of Medicine (shares tenth place with Imperial College London Faculty of Medicine)

These aside, there are also easy medical schools to get into which might not offer the same prestige as the ones mentioned above but still provide competitive programs for those who aspire to become doctors.

How long does it take to become a licensed doctor?

For students who want to become doctors, the real journey begins in medical school. In the four years that they spend in medicine proper, they have in-depth courses on anatomy and physiology. They take more classes on biochemistry, pathology, and microbiology. They also have subjects exploring psychiatry and community health.

However, graduating from a medical school does not mean that a person can already apply for a license to practice the profession. They still need to undergo residency training, which ranges from three to seven years, depending on the specialization that a doctor chooses. There are also specializations wherein students spend one transitional or preliminary year (Washington University School of Medicine in St. Louis, n.d.).

Overall, before an individual becomes a full-fledged doctor, they have to study for at least eleven years.

Source: Washington University School of Medicine in St. Louis

How much do doctors earn?

Since the onset of the novel coronavirus, physicians have experienced a 55% decrease in revenue and a 60% decrease in the number of patients. Because of that, 9% of independent medical practices closed their clinics, albeit temporarily (Kane, 2020).

The COVID-19 crisis is impacting the health industry greatly, even as private practices are beginning to get back on their feet. Prior to the coronavirus pandemic, primary care physicians (PCP) would have an average income of $243,000 per year. On the other hand, specialists could take home an average of $346,000 annually (Kane, 2020).

In the previous year, PCPs only looked at an average income of $237,000 per annum. This translates to a 2.5% increase this 2020. Similarly, the average earnings of specialists also increased by 1.5% from 2019 (Kane, 2020). Even the entry level dentist salary has been similarly affected.

Out of all specialists, orthopedicians are the most generously compensated, taking home an average of $511,000 per year. The specialists with the lowest average income are the pediatricians and public health and preventive medicine physicians, who have an average income of $232,000 yearly (Kane, 2020). However, according to another report, neurosurgeons are the highest compensated specialists, as they would have an average income of $616,823 per year. Among the top ten highest-earning specialists, radiologists are at the bottom of the rung with an average salary of $428,572 (Doximity, 2019).

Source: Kane, 2020

Famous People Who Studied Medicine

Though they went on to pursue different professions, the people listed below did study medicine or completed a degree in a medical field. Some of them even practiced it before they took another career path. And there are also those who went to medical schools for a bit before diverging.

  • Ernesto "Che" Guevara - Argentine revolutionary, completed his medical studies in 1953 from Universidad de Buenos Aires.
  • Graham Chapman - A founding member of Monty Python, he attended St. Bartholomew's Medical College in London but abandoned his medical studies.
  • Phillip Calvin McGraw - Dr. Phil, television celebrity, is indeed a doctor. He was licensed to practice psychological therapy but ceased renewing it in 2006.
  • Michael Crichton - Known to be the brains behind Jurassic Park, the immensely successful author graduated from Harvard Medical School. However, he never practiced medicine.
  • Kamaljeet Singh Jhooti - Better known as Jay Sean, he enrolled in the medicine program of Queen Mary University of London though he abandoned his studies to become a singer.
  • Deepak Chopra - A famous figure in the New Age movement, he was a senior cardiologist, a surgeon, and a medical advisor to the last viceroy of India.
  • Mayim Bialik - Most people know her as Dr. Amy Farrah on Big Bang Theory. She graduated from UCLA with a BSc in Neuroscience, Hebrew Studies, and Jewish Studies. She also completed her Ph.D. at UCLA.
  • Lisa Kudrow - She was successful Phoebe in Friends but while taking a break from acting, she finished a psychobiology degree at Vassar College.
  • Kendrick Kang-Joh Jeong - Now a comedian, Ken Jeong finished his MD studies at the University of North Carolina at Chapel Hill. He practiced medicine at Kaiser Permanente in Woodland Hills but stopped doing so in favor of a career in show business. He remains a licensed physician.

Doctors in the Time of COVID-19

The novel coronavirus has been a real challenge to doctors and scientists alike. Since it is a new disease, and now a pandemic, too, it has proven difficult to crack it and to develop a vaccine to immunize the population. While most doctors are unable to actively help in finding a cure or a vaccine, but they can provide data and analytics to the U.S. Centers for Disease Control and Prevention. Doctors in other countries can also give insights to their respective health agencies. This is a vital step, as it can aid in preventing the further spread of any communicable disease.


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