Letter of Recommendation Characteristics Associated with Interview Offer to a Vascular Surgery Residency Program

Background: Letters of recommendation (LOR) are considered by program directors (PDs) to be an integral part of the residency application. With the conversion of United States Medical Licensing Examination (USMLE) Step 1 to a binary pass/fail outcome, LORs will likely have higher important in the application process moving forward. However, their utility in securing an interview for a particular applicant remains undetermined. This study aims to identify the applicant and LOR characteristics associated with an interview invitation. Methods: Letter writer (n = 977) characteristics were abstracted from applications (n = 264) to an individual integrated vascular surgery residency program over 2 application cycles. A validated text analysis program, Linguistic Inquiry and Word Count, was used to characterize LOR content. Applicant, letter writer, and LOR characteristics associated with an interview invitation were determined using multivariable analysis. Results: Letter writers were 70.9% vascular surgeons (VS), 23.7% PDs, and 45.4% professors. Applicants offered an interview were more likely to come from a top 50 medical school (35.2% vs 25.8%, P = 0.013) and an institution with a home vascular program (45.5% vs 34.1%, P = 0.006). Alpha Omega Alpha membership was significantly associated with interview offer (28.4%, P < 0.001). A greater proportion of letters from VS was associated with an interview offer (P < 0.001) compared with letter writers of other specialties. One or more PD letters were significantly associated with an interview offer (79.55% vs 20.45%, P = 0.008), whereas number of letters from APDs was not significantly associated with interview offer. Letters written by away institution faculty were significantly associated with interview offer (75%, P < 0.001), whereas nonclinical letters were not. Presence of one or more letters from a chair (57.95% vs 42.05%, P = 0.015) or chief (67.05% vs 32.95%, P = 0.028) was significantly associated with interview offer. Letters for applicants offered an interview had more references to research and teaching, which were more common in letters written by versus Letters written by PDs were more likely to use assertive, advertising language in favor of applicants. There were no significant applicant, letter writer, or LOR characteristics associated with a top 20 rank. Conclusions: Successful applicants were more likely to have LORs written by VS, PDs, and those of higher academic rank with references to research and teaching.