Many preference signals as a soft cap on number of applications in medical residency matching

 Here's a review article on matching for medical residents,  with particular attention to neurosurgery, in the Cureus Journal of Medical Science.  In specialties that (like neurosurgery) allow applicants to send many signals, many applicants signal to and match with programs with which they have some prior connection.

Ozair, Ahmad, Jacob T. Hanson, Donald K. Detchou, Matthew P. Blackwell, Abigail Jenkins, Marianne I. Tissot, Umaru Barrie et al. "Program Signaling and Geographic Preferences in the United States Residency Match for Neurosurgery." Cureus 16, no. 9 (2024).

Abstract: Postgraduate residency training has long been the cornerstone of academic medicine in the United States. The Electronic Residency Application Service (ERAS), managed by the Association of American Medical Colleges (AAMC), is the central residency application platform in the United States for most clinical specialties, with the National Residency Matching Program (NRMP) being the algorithm for matching residency programs with applicants. However, the determination of the best fit between ERAS applicants and programs has been increasingly challenged by the rising number of applicants per residency spot. This application overburdening across competitive specialties led to several adverse downstream effects, which affected all stakeholders. While several changes and proposals were made to rectify the issue of application overburdening, the 2020-2021 ERAS Match Cycle finally saw several competitive specialties, including otolaryngology and urology, utilize a new system of supplemental residency application based on preference signals/tokens. These tokens permit applicants to electronically signal a select number of programs in a specialty of choice, with the program reviewing the application now cognizant that they have been signaled, i.e., the applicant has chosen to use up a limited set of signals for their program. Initial results from otolaryngology and urology, as described in this article, indicated the value of this new system to both applicants and educators. Given the favorable outcomes and broader uptake of the system among other specialties, the field of neurosurgery adopted the utilization of the ERAS-based program signaling and geographic preference for the first time for the 2022-2023 Residency Application Cycle and later opted to continue them for the 2023-2024 and 2024-2025 cycles. For the 2024-2025 Match Cycle, neurosurgery applicants have 25 signals, i.e., a "high-signal" approach, where non-signaled programs have a low interview conversion rate. This literature review discusses the rationale behind the change, the outcomes of other competitive specialties from prior cycles, the evolving nature of the change, and the potential impact on applicants and programs. As we describe in this review, signaling may potentially represent a surrogate form of an application cap. Other considerations relate to cost savings for both applicants and programs from a high-signal approach in neurosurgery. These modifications represent a foundational attempt to alleviate the application overburdening and non-holistic review in the residency application process, including for neurosurgery. While these changes have been a welcomed addition for all stakeholders in residency match cycles so far, further prospectively directed surveys along with qualitative research studies are warranted to better delineate the downstream impact of these changes and guide further optimization of the application system.