Cumulative Sum Chart as Complement to Objective Assessment of Graduating Surgical Resident Competency: An Exploratory Study

BACKGROUND: Rater-based assessment and objective assessment play an important role in evaluating residents’ clinical competencies. We hypothesize that a cumulative sum (CUSUM) chart of operative time is a complement to the assessment of chief general surgery residents’ competencies with ACGME Milestones, aiding residency programs’ determination of graduating residents’ practice readiness. STUDY DESIGN: We extracted ACGME Milestone evaluations of performance of operations and procedures (POP) and 3 objective metrics (operative time, case type, and case complexity) from 3 procedures (cholecystectomy, colectomy, and inguinal hernia) performed by 3 cohorts of residents (N = 15) during their PGY4-5. CUSUM charts were computed for each resident on each procedure type. A learning plateau was defined as at least 4 cases consistently locating around the centerline (target performance) at the end of a CUSUM chart with minimal deviations (range 0 to 1). RESULTS: All residents reached the ACGME graduation targets for the overall POP by the end of chief year. A total of 2,446 cases were included (cholecystectomy N = 1234, colectomy N = 507, and inguinal hernia N = 705), and 3 CUSUM chart patterns emerged: skewed distribution, bimodal distribution, and peaks and valleys distribution. Analysis of CUSUM charts revealed surgery residents’ development processes in the operating room towards a learning plateau vary, and only 46.7% residents reach a learning plateau in all 3 procedures upon graduation. CONCLUSIONS: CUSUM charts of operative time complement the ACGME Milestones evaluations. The use of both may enable residency programs to holistically determine graduating residents’ practice readiness and provide recommendations for their upcoming career/practice transition.