Academic Medicine

The 2023 Internal Medicine Fellowship Match

The results of the 2023 internal medicine subspecialty fellowship match (for positions to start July 2024) were released last week. Once again, there were lessons to be learned about which subspecialties are competitive and which are unpopular. The results are published on-line on the National Residency Match Program website. Overall, there were 6,001 internal medicine subspecialty fellowship positions available and 88.4% were filled in the match. Of those physicians who did match to a fellowship position, 47% were U.S. MD graduates, 26.2% were foreign medical graduates, 13.3% were U.S. graduates of international medical schools, 12.8% were U.S. DO graduates, and 0.2% were Canadian medical school graduates.

The greatest number of available fellowship positions were in cardiology (1,199), pulmonary/critical care (781), hematology/oncology (712), and gastroenterology (582) as shown in the graph below:

The most and least popular subspecialties

The most popular subspecialty fellowships are those that have the highest percentage of available positions that fill in the match, as shown in the graph below. In some subspecialties (endocrinology, gastroenterology, hematology/oncology, and nephrology), there is both a clinical and a research fellowship pathway, each with its own match. For those fellowships, only the clinical pathway statistics are included in this analysis.

Internal medicine subspecialties that filled >99% of available positions included: allergy, cardiology, gastroenterology, and hematology/oncology. These are very competitive subspecialties and many applicants were unable to match to an available position. The percentage of applicants who matched to an open fellowship position were: allergy – 72.0%, cardiology – 66.8%, gastroenterology – 65.5%, and hematology/oncology – 77.5%.

The least competitive subspecialties were addiction medicine, geriatrics, infectious disease, and nephrology. All of these filled less than 70% of available fellowship positions. This is similar to last year’s internal medicine subspecialty fellowship match when these subspecialties also had a low percentage of available positions fill in the match. Nearly all residents who applied to these fellowships matched somewhere. The percentage of applicants who matched were: addiction medicine – 92.5%, geriatrics – 96%, infectious disease – 96.7%, and nephrology – 93.9%.

Pulmonary and critical care medicine is unique among the subspecialties in that there are critical care-only fellowships (2 years; 187 available positions), pulmonary-only fellowships (2 years; 31 available positions), and combined pulmonary/critical care fellowships (3 years; 781 available positions). Most applicants choose the combined fellowship because it provides greater career flexibility.

Foreign medical graduates and subspecialties

There are five training pathways to become a practicing physician in the United States: (1) U.S. MD graduates, (2) U.S. DO graduates, (3) U.S. citizens who attend international medical schools, (4) Canadian medical school graduates, and (5) foreign medical graduates. In general, graduates of U.S. medical schools (MD) and osteopathic schools (DO) are considered more competitive than applicants who attended a non-U.S. medical school. Because most subspecialty fellowships are affiliated with medical schools (as opposed to osteopathic schools), MD graduates are often seen as more competitive than DO graduates. U.S. citizens who attended international medical schools are generally less competitive and foreign medical graduates are often the least competitive.

Therefore, one might think that the subspecialties that fill with the highest percentage of U.S. MD graduates are generally the most competitive whereas those subspecialties that fill with a high percentage of foreign medical graduates are seen as less competitive. However, this is not always the case and there are other factors that determine the percentage of U.S. MD graduates versus foreign medical graduates that successfully match to a subspecialty fellowship position.

Subspecialties with the highest percentage of positions filled by U.S. MD graduates were addiction medicine, allergy, and palliative medicine. These subspecialties had fewer than 10% of available positions filled by foreign medical graduates. Three subspecialties had more foreign medical graduates than U.S. MD graduates match to available positions: endocrinology, nephrology, and pulmonary.

DO graduates and subspecialties

Osteopathic schools have a slightly different educational philosophy than medical schools with greater emphasis on the musculoskeletal system and on primary care. As a result, certain subspecialties tend to attract more DO graduates than others.

Specialties with the highest percentages of U.S. DO graduates were palliative medicine, nephrology, critical care medicine, and addiction medicine. On the other hand, hematology/oncology and pulmonary had the lowest percentage of available positions filled by U.S. DO graduates.


There are 4 fellowships that participate in the internal medicine subspecialty match that are subspecialties of a subspecialty. That is, they require initial completion of a subspecialty fellowship in order to apply. These include three subspecialties of cardiology and one subspecialty of pulmonary (or pulmonary/critical care).

  • Adult congenital heart disease. There were 26 available positions and 53.8% of these were filled. All applicants were able to match to an available position and 78.6% of matched applicants were U.S. MD graduates.
  • Advanced heart failure and transplant cardiology. There were 129 available positions and 56.6% of these were filled. Overall, 87.8% of applicants matched to an available position and 56.2% of them were U.S. MD graduates.
  • Clinical cardiac electrophysiology. There were 145 available positions and 96.6% of these were filled. Overall, 87.5% of applicants matched to an available position and 52.1% were U.S. MD graduates.
  • Interventional pulmonary. There were 43 available positions and all of these were filled. Overall, 69.4% of applicants matched to an available position and of these, 32.6% were U.S. MD graduates.

There are some sub-subspecialties that do not participate in the regular internal medicine subspecialty match. Interventional cardiology has historically filled positions outside of the match but will join the regular subspecialty match in 2024 (for the 2025 appointment year). Hepatology is a subspecialty of gastroenterology and fills fellowship positions outside of the regular match. Sports medicine fellowships can be obtained after completion of either a family medicine, internal medicine, emergency medicine, physical medicine, or pediatric residency and fills positions in its own separate match.

Some take-away points

The annual subspecialty fellowship match offers insight into what young physicians consider to be desirable versus undesirable subspecialty career choices. The popularity of a given subspecialty is a complex interplay between work-life balance, mentor influence, patient characteristics, excitement of recent disease management breakthroughs, and future income. In a previous post, I analyzed physician income per year of residency/fellowship training. A summary of those findings for internal medicine subspecialties based on the MGMA non-academic compensation data is seen in the two graphs below:

Here are some thoughts about the fellowship match results for specific subspecialties.

  • Nephrology. For several years, many available nephrology fellowship positions have remained unfilled and this year was no exception with only 63.1% of positions filled. Of those positions that were filled, the majority were by graduates of non-U.S. medical schools (37.3% foreign medical graduates + 21.8%  U.S. citizen graduates of international medical schools). It is likely that in the future, there will be a shortage of nephrologists and most of those in practice will not have trained in a U.S. medical or osteopathic school. The reason for nephrology’s lack of popularity is partly financial – nephrologists’ total income is slightly below average for internal medicine subspecialties but about average when viewed as income per year of training. Other reasons may include an undesirable work-life balance (frequent weekends and frequent night-call emergencies) and a metabolically complex, chronically ill patient population that can often be frustrating to manage. In addition, residents from U.S. medical and osteopathic schools may not be as strongly influenced by attending physician mentors who trained abroad due to language and cultural differences. As nephrology becomes increasingly dominated by foreign medical graduates, these differences could impact subspecialty choice by U.S. medical and osteopathic school graduates.
  • Geriatrics. As with nephrology, a medically complex and chronically ill patient population may be seen by some residents as a deterrent to choosing geriatrics as a career. A bigger reason, however, is financial – geriatricians have a lower total income than general internists or internal medicine hospitalists, despite having more years of training. In fact, geriatricians have the lowest income of all internal medicine subspecialties. These factors contribute to geriatric fellowships having the lowest fill rate in the match at 44.5%
  • Infectious disease. Another subspecialty that has regularly failed to fill in recent years is infectious disease. One of the reasons for this is financial – infectious disease specialists have a relatively low total income compared to other internal medicine subspecialties and when viewed as income per years of training, it is one of the lowest. For the time cost of 2 additional years of residency/fellowship training, infectious disease physicians have a total annual income similar to that of hospitalists and general internists. In addition, a large percentage of infectious disease clinical practice is inpatient and as a result, these physicians tend to work more weekends and holidays than general internists and other subspecialists which can contribute to a less desirable work-life balance. Lastly, infectious disease specialists have felt vilified by a significant percentage of Americans during the COVID pandemic who saw them as the messengers of vaccine mandates, school closings, and pandemic-related public health restrictions. For these Americans, infectious disease is derogatorily seen as “Fauci-ism”.
  • Addiction medicine. There are several pathways to doing an addition medicine fellowship – internal medicine, pediatrics, and psychiatry. The data in this post is for the internal medicine pathway but the statistics for addiction psychiatry fellowships are similar. Addiction medicine had the second lowest match fill rate (55.9%) after geriatrics. However, it paradoxically also had one of the lowest percentages of foreign medical graduates matching to available positions. Possible reasons for this could include lack of awareness of addiction medicine as an internal medicine subspecialty by foreign medical graduates and bias against foreign medical graduates by addiction medicine fellowship programs. Also contributing to its low fill rate is a patient population that is often uninsured or covered only by Medicaid, a high percentage of patients who relapse after treatment, and a misperception by some physicians that addiction is a behavioral choice rather than a true disease.
  • Palliative medicine. The fill rate in the match was relatively low (83.1%) but like addiction medicine, very few foreign medical graduates matched in palliative medicine. The reasons for the low fill rate likely includes high burn-out rate among palliative medicine physicians, low income, and frequently weekend/night call duties.
  • Endocrinology. Although fairly successful in the match with 91.7% of available fellowship positions filled, endocrinology was one of only three subspecialties that filled with more foreign medical graduates (37.0%) than U.S. MD graduates (29.6%). When also including U.S. citizens who trained in international medical schools (20.3%), it is apparent that in the future, the majority of endocrinologists will not have trained at a U.S. medical or osteopathic school. One of the drivers of endocrinology’s unpopularity among graduates of U.S. medical schools is financial – endocrinologists have a total income of less than that of hospitalists or general internists, despite having to complete two more years of fellowship training.
  • Cardiology, gastroenterology, and pulmonary/critical care. These three subspecialties did quite well in the match with > 98% of available positions filled and the majority of positions filled by either U.S. MD or DO graduates. As opposed to other internal medicine subspecialties, these three incorporate a large amount of procedures and also have higher total incomes. These factors contribute to their popularity.
  • Hematology/oncology, allergy, and rheumatology. These three subspecialties also continue to be very popular, filling > 98% of available positions. Allergists and rheumatologists have total incomes that are lower than many internal medicine subspecialties but they have a very desirable work-life balance with little inpatient responsibilities, little night call, and little weekend rounding. Hematology/oncology is attractive to residents because of the rapid development of exciting new cancer treatments in recent years coupled with a relatively high annual income.

Some final thoughts…

If I had to pick one subspecialty to worry about from this year’s fellowship match, it would be infectious disease. Because of low pay and long work weeks, we are seeing fewer and fewer physicians choose infectious disease as a career. The economics of physician reimbursement from Medicare and commercial health insurance is unfavorable to infectious disease and as long as physician reimbursement models are unchanged, infectious disease will remain unattractive to young physicians. Hospitals must be willing to financially supplement infectious disease specialists to a greater extent than other specialists. This could take the form of call-pay, weekend-pay, or other non-RVU-based compensation. If HIV, SARS, H1N1, and COVID are any indication, the next pandemic is just around the corner.

Fellowship funding is complex with sources from Medicare graduate medical education funds, hospital general funds, college of medicine funds, research grants, and attending physician professional revenue. However, regardless of the sources, the cost of fellow salaries and benefits must be included in the annual budgets of teaching hospitals. In addition, there are indirect costs such as release time funding for fellowship program directors and administrative staff which must also be budgeted for. The results of this year’s subspecialty fellowship match suggests that hospitals would be better off reducing the number of fellowship positions in addiction medicine, geriatrics, and nephrology since these subspecialties have a large number of unfilled positions. Indeed, it may make more financial and budgetary sense for hospitals with small numbers of fellows in these subspecialties to eliminate that fellowship program entirely. This would allow hospitals to increase the number of fellowship positions in subspecialties such as allergy, cardiology, gastroenterology, hematology/oncology, pulmonary/critical care, and rheumatology.

Subspecialty fellowships do not respond to the free market laws of supply and demand. It is up to our nation’s hospitals to make decisions about supplementing income for subspecialists such as infectious disease physicians and about reducing the size or closing fellowships in geriatrics, addiction medicine, and nephrology. Each hospital should look critically at the trend in fill rates of its subspecialty fellowship matches from recent years.

December 4, 2023

By James Allen, MD

I am a Professor Emeritus of Internal Medicine at the Ohio State University and former Medical Director of Ohio State University East Hospital