The research team, led by Sohail Khan of Touro College of Osteopathic Medicine together with collaborators at George Mason University, Stony Brook Medicine, Columbia University and other institutions, constructed a cross-sectional cohort of 892 directors. It included 179 medical student clerkship directors, 366 general surgery residency program directors, and fellowship directors in complex general surgical oncology, surgical critical care, minimally invasive surgery and endocrine surgery. Leadership identities were compiled from publicly available sources and national accreditation databases, including the Liaison Committee on Medical Education, the Accreditation Council for Graduate Medical Education, the National Resident Matching Program and the American Medical Association’s FREIDA database, supplemented by the Fellowship Council and the American Association of Endocrine Surgeons.

Demographic characteristics were ascertained using automated facial analysis with investigator adjudication, an approach that has become increasingly common in workforce diversity research where self-reported race and gender data are unavailable for public-facing professionals. The team used the Betaface API, version 2.0, with human reviewers confirming classifications. Categorical comparisons relied on Pearson chi-squared and Fisher exact tests, while multivariable logistic regression identified factors independently associated with holding leadership roles. All analyses were performed in STATA version 18E. Because the study relied exclusively on publicly available, aggregated data with no patient-level or identifiable private information, institutional review board approval was deemed exempt.

The headline numbers are unambiguous. Among the 892 directors, White surgeons predominated at 67.8 percent, followed by Asian surgeons at 18.2 percent, Middle Eastern surgeons at 5.3 percent, Hispanic surgeons at 4.8 percent and Black surgeons at 3.9 percent. Female representation across the entire cohort stood at 34.5 percent, but the figure varied dramatically by subspecialty, a difference that reached statistical significance at P less than .001. Endocrine surgery led the way with 48.0 percent female fellowship directors, while minimally invasive surgery sat at the bottom with just 20.3 percent. Asian surgeons were most visible at the fellowship tier in complex general surgical oncology, at 31.4 percent, and endocrine surgery, at 24.0 percent, while international medical graduates were most prevalent among directors in complex general surgical oncology at 20.0 percent and minimally invasive surgery at 18.3 percent.

Perhaps the most revealing structural signal came from academic rank. Rank distribution differed markedly across leadership tiers, again with P less than .001. Assistant professors constituted the plurality of clerkship directors at 44.1 percent, suggesting that the entry point of the educational pipeline is staffed disproportionately by junior faculty. At the opposite end, full professors were most common among fellowship directors in complex general surgical oncology at 40.0 percent and minimally invasive surgery at 33.3 percent. Institutional setting followed a similar gradient: residency program directors were predominantly community-based at 58.8 percent, whereas fellowship directors were primarily university-based. In other words, as leadership roles become more senior and more concentrated in elite academic centers, they become demographically narrower.

The pipeline benchmarking makes the attrition vivid. Between 2022 and 2025, across 214,411 medical school applicants and 5,988 matched general surgery residents, women accounted for 56.8 percent of applicants and 55.1 percent of matched residents. Black trainees represented 9.4 percent of matriculants and 7.2 percent of matched residents, and Hispanic trainees 6.4 percent of matriculants and 12.0 percent of matched residents. Every one of those proportions exceeds the corresponding group’s share of surgical education leadership. Black surgeons, at 3.9 percent of directors, hold leadership roles at less than half their rate of residency entry. Hispanic surgeons, at 4.8 percent of directors, fare even worse against their 12.0 percent share of matched residents. Women, the statistical majority of incoming residents, remain a one-third minority of directors overall and barely one in five in minimally invasive surgery.

The authors frame this discordance as demographic consolidation within senior academic ranks and university-based institutions across the surgical training continuum. The mechanism is consistent with the well-documented leaky pipeline literature cited in the study, which traces how underrepresented-in-medicine trainees encounter compounding barriers from undergraduate education through faculty advancement. Prior work has shown that mentorship alone is insufficient without active sponsorship, that early-career scholarly productivity gaps set the stage for unequal academic advancement, and that leadership demographics of training programs are themselves associated with trainee diversity. A leadership tier that does not reflect the trainees beneath it risks perpetuating itself, since directors control recruitment, evaluation, promotion and the informal networks through which opportunities flow.

The timing of the study lends it particular urgency. The published literature it draws on includes recent warnings that health care has become a new battlefront for anti-diversity, equity and inclusion attacks, and that anti-DEI legislation threatens both equitable surgical care and workforce diversity. In that climate, the study’s demonstration that gains at the trainee level are not being converted into governance-level representation provides an empirical baseline against which any policy retreat or advance can be measured. It also matters for patients: prior research has linked surgeon sex to long-term postoperative outcomes for common operations, and a diverse physician workforce is associated with improved trust and communication among racially and ethnically diverse patient populations.

Methodologically, the continuum-wide design is what distinguishes this analysis from earlier single-tier studies. Previous investigations have examined gender gaps among residency program leadership, diversity within individual fellowship directorships, or racial trends in specific subspecialty pipelines, but few have connected clerkship, residency and fellowship leadership into a single cross-sectional frame and benchmarked each tier against national applicant and match data. That design exposes the gradient directly: diversity is highest where the pipeline is widest and lowest where the funnel is narrowest, with the fellowship director tier, the most university-concentrated and most senior, showing the greatest consolidation. The subspecialty contrasts are equally instructive, since endocrine surgery’s near-parity female leadership and complex surgical oncology’s relatively high Asian and international medical graduate representation demonstrate that different structural cultures within surgery produce different outcomes from the same national pipeline.

The study’s limitations are those inherent to its design. Facial analysis, even with investigator adjudication, is an imperfect proxy for self-identified race and gender, and the cross-sectional snapshot cannot establish causation or track individuals over time. The fellowship analysis covers four subspecialties rather than the full breadth of surgical fellowship training. Still, the data availability statement notes that all figures derive from publicly accessible sources and are included in the published article and its supplementary files, making the findings independently verifiable. What the analysis delivers is a precise, reproducible map of where the surgical education system loses its diversity, and the map points unambiguously to the terminal bottleneck: the senior, university-based directorships that shape who enters the profession, how they are trained, and who among them will one day hold the levers of surgical governance. Until representation at that tier reflects the majority-female, increasingly diverse residency cohorts now moving through the pipeline, the study suggests, the demographic gains of the past decade will remain stranded at the bottom of the ladder.

Subject of Research: Demographic and structural disparities in U.S. surgical education leadership across the training continuum

Article Title: The terminal bottleneck: a continuum-wide cross-sectional analysis of demographic and structural disparities in U.S. surgical education leadership (2025–2026)

Article References: The terminal bottleneck: a continuum-wide cross-sectional analysis of demographic and structural disparities in U.S. surgical education leadership (2025–2026). (n.d.). https://doi.org/10.1007/s44186-026-00548-w

Image Credits: AI Generated

DOI: 10.1007/s44186-026-00548-w

Keywords: surgical education, leadership diversity, academic surgery, workforce disparities, gender equity, underrepresented in medicine, fellowship directors, residency program directors, clerkship directors, leaky pipeline, medical education, health equity