Socioeconomic Diversity in Admissions to MD-PhD Programs, 2014-2019

Physician-scientists play a unique role in translating research to clinical practice. Diversity among physician-scientists is essential for biomedical innovation and equitable health care.¹ MD-PhD training programs represent a critical pathway for the development of physician-scientists. Although first-generation college students have been less likely to be accepted into MD-PhD programs,² little is known about how application and acceptance rates vary across household income. This study aims to examine trends in application and acceptance to MD-PhD program by family income. Methods We conducted a retrospective cohort study of applicants to US MD-PhD programs between 2014 and 2019 using deidentified data from the Association of American Medical Colleges. Data and descriptive statistics are described in Supplement 1. We estimated the relative risk of acceptance to at least 1 MD-PhD program across income using modified Poisson regression with robust error variance, adjusting for students’ self-reported race, ethnicity, sex, grade point average, Medical College Admission Test results, number of publications, and total MD-PhD programs applications sent. Statistical significance was 2-sided with P < .05 indicating statistical significance, and analyses were performed in July 2023 using Stata version 18.0 (StataCorp LLC). We followed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) reporting guideline. This study was deemed exempt by the Yale institutional review board, and informed consent requirements were waived because data were deidentified. Results Between 2014 and 2019, 10 953 students applied to MD-PhD programs. Of these, 4724 students (43.1%) were female; 5020 (52.1%) were White, 2243 (23.3%) Asian, and 805 (8.4%) multiracial. Among MD-PhD applicants, 4959 (45.3%) were accepted into 1 or more MD-PhD program. The percentage of applicants reporting household income less than $50 000 decreased annually, from 28.36% in 2014 to 25.14% in 2019 (annual percent change [APC], −0.57%; 95% CI, −0.94% to −0.21%; P = .01) (Figure 1). No significant change was found for other income categories. In contrast, the percentage of accepted students reporting household income greater than $200 000 increased annually, from 16.10% in 2014 to 20.87% in 2019 (APC, 0.90%; 95% CI, 0.08% to 1.72%; P = .03), with no significant change for other income categories. Combining applicants across all years, while 50.3% of applicants from household income greater than $200 000 were accepted to MD-PhD programs, only 29.9% of applicants from household income less than $50 000 were accepted (Figure 2). In the fully adjusted model, applicants from household income less than $50 000 were 16% less likely than their peers to be accepted into an MD-PhD program (adjusted relative risk, 0.84; 95% CI, 0.79-0.90).