Evaluating Neurosurgery Resident Competency: A Comparative Study of Milestones 1.0 and 2.0 Across 10 Years

The Accreditation Council for Graduate Medical Education Neurosurgery Milestones were implemented to advance competency-based training in neurosurgery; however, research on milestones in neurosurgery has been more limited, and there has been no comprehensive study on the milestone ratings and the comparability of Milestones 1.0 and 2.0. The goal of this study was to describe the levels and trends of competency ratings across Milestones 1.0 and 2.0 for neurosurgical residents in the United States over the decade of implementation. Milestones 1.0 and 2.0 cover both nontechnical competencies and critical technical skills.

We conducted a retrospective analysis of milestone assessments from 2013 to 2023 across 124 US neurosurgery residency programs, encompassing both Milestones 1.0 (2013-2018) and Milestones 2.0 (2018-2023). We used descriptive statistics to examine the distributions of milestone ratings and identify performance trends in milestone ratings across postgraduate year (PGY) levels.

The highest average rating across any milestone and all PGY levels in Milestones 1.0 was professionalism (mean = 3.17, SD 1.02) whereas the average resident rating for Patient Care was the lowest (mean = 2.89, SD = 1.03). However, a shift occurred for Milestones 2.0 where Interpersonal and Communication Skills became the highest for early PGY levels and Medical Knowledge for senior residents. Patient Care remained the lowest scoring competency under both systems. Subcompetencies such as Critical Care and Brain Tumor management consistently showed high scores, whereas areas such as Surgical Treatment of Epilepsy, Pain and Peripheral Nerves, and Pediatric Neurosurgery demonstrated lower scores.

A balance between nontechnical competencies and critical technical skills is necessary to ensure comprehensive neurosurgical training. Established benchmarks can enhance the utility of milestone data and support the development of well-rounded, competent neurosurgeons.