BackgroundInitiatives employing medical students’ volunteerism and idealism, such as the Student-Run Free Clinics (SRFC) program, are prevalent in US medical schools. Many studies evaluated various aspects of volunteering, sometimes resulting in conflicting evidence. This study simultaneously sought to identify the characteristics of volunteers vs. non-volunteers, and to characterize the volunteers’ perception of the SRFC.MethodsWe administered a survey to the Long School of Medicine (LSOM) Class of 2018 before their third year of medical school. The authors compared and contrasted the findings of the SRFC volunteers with their non-volunteering counterparts by analyzing their demographics, volunteering history, academic performance, and clinical skills. The volunteers were also asked about their SRFC experiences.ResultsWhile most volunteers were female (62 %) and non-traditional students (67 %), the difference was not statistically significant (p = 0.15 and p = 0.38, respectively). Additionally, there were no statistically significant differences between the two groups in measures of academic performance (p = 0.25). Most of the volunteers learned about the SRFC program prior to starting medical school. Further, while SRFC volunteers were more likely to engage in additional local volunteering initiatives, the difference was not statistically significant (p = 0.03, prespecified α= 0.006). Importantly, volunteers agreed/strongly agreed that SRFC volunteering emphasized aspects that were missing or underemphasized in the formal medical school curriculum.ConclusionsMedical students’ age, gender, undergraduate major, and non-traditional status were not statistically different between volunteers vs. non-volunteers. However, there may be tendencies for volunteers to be female, non-traditional, and locally engaged. Further, the timing of knowledge of the SRFC program may not affect student involvement in the SRFC, either. Most importantly, however, while volunteering does not affect the students’ academic performance, it may provide improvements in clinical competencies.