Optimizing the Volume-Value Relationship in Laminectomy: An Evidence-Based Analysis of Outcomes and Economies of Scale.

STUDY DESIGN: Retrospective cohort study.

OBJECTIVE: The objective of the present study was to establish evidence-based volume thresholds for surgeons and hospitals predictive of enhanced value in the setting of laminectomy.

SUMMARY OF BACKGROUND DATA: Previous studies have attempted to characterize the relationship between volume and value, however, none to the authors' knowledge have employed an evidence-based approach to identify thresholds yielding enhanced value.

METHODS: 67,758 patients from the New York Statewide Planning and Research Cooperative System (SPARCS) database undergoing laminectomy in the period 2009-2015 were included. We used stratum-specific likelihood ratio (SSLR) analysis of receiver operating characteristic (ROC) curves to establish volume thresholds predictive of increased length of stay (LOS) and cost for surgeons and hospitals.

RESULTS: Analysis of LOS by surgeon volume produced strata at: <17 (low), 17-40 (medium), 41-71 (high), and >71 (very high). Analysis of cost by surgeon volume produced strata at: <17 (low), 17-33 (medium), 34-86 (high), and >86 (very high). Analysis of LOS by hospital volume produced strata at: <43 (very low), 43-96 (low), 97-147 (medium), 148-172 (high), and >172 (very high). Analysis of cost by hospital volume produced strata at: <43 (very low), 43-82 (low), 83-115 (medium), 116-169 (high), and >169 (very high). LOS and cost decreased significantly (p < 0.05) in progressively higher volume categories for both surgeons and hospitals. For LOS, medium-volume surgeons handle the largest proportion of laminectomies (36%), whereas very high-volume hospitals handle the largest proportion (48%).

CONCLUSIONS: This study supports a direct volume-value relationship for surgeons and hospitals in the setting of laminectomy. These findings provide target-estimated thresholds for which hospitals and surgeons may receive meaningful return on investment in our increasingly value-based system. Further value-based optimization is possible in the finding that while the highest volume hospitals handle the largest proportion of laminectomies, the highest volume surgeons do not.

LEVEL OF EVIDENCE: 3.