Evidence-based thresholds for the volume-value relationship in shoulder arthroplasty: outcomes and economies of scale

• Published in: Journal of shoulder and elbow surgery 2017-08, Vol.26 (8), p.1399-1406
• Main Authors: Ramkumar, Prem N., Navarro, Sergio M., Haeberle, Heather S., Ricchetti, Eric T., Iannotti, Joseph P.
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; arthroplasty; Arthroplasty, Replacement, Shoulder - adverse effects; Arthroplasty, Replacement, Shoulder - economics; Clinical Competence; cost; Costs and Cost Analysis; Female; Health Care Costs - statistics & numerical data; Hemiarthroplasty - adverse effects; Hemiarthroplasty - economics; Hospitals, High-Volume - statistics & numerical data; Hospitals, Low-Volume - statistics & numerical data; Humans; length of stay (LOS); Length of Stay - economics; Length of Stay - statistics & numerical data; Male; Middle Aged; Orthopedic Surgeons - statistics & numerical data; Osteoarthritis - surgery; outcomes; receiver operating characteristic (ROC); Reference Values; ROC Curve; Shoulder; Shoulder Joint - surgery; threshold; volume; Young Adult
• ISSN: 1058-2746; 1532-6500
• DOI: 10.1016/j.jse.2017.05.019

Whereas several studies suggest that high-volume surgeons and hospitals deliver superior patient outcomes with greater cost efficiency, no evidence-based thresholds separating high-volume surgeons and hospitals from those that are low or medium volume exist in shoulder arthroplasty. The objective of this study was to establish meaningful thresholds that take outcomes and cost into consideration for surgeons and hospitals performing shoulder arthroplasty. Using 9546 patients undergoing primary shoulder arthroplasty for osteoarthritis from an administrative database, we created and applied 4 models using stratum-specific likelihood ratio (SSLR) analysis of a receiver operating characteristic (ROC) curve. We generated 4 sets of thresholds predictive of adverse outcomes, namely, increased length of stay (LOS) and increased cost for both surgeon and hospital volume. SSLR analysis of the 4 ROC curves by surgeon volume produced 3 volume categories. LOS and cost by annual shoulder arthroplasty surgeon volume produced the same strata: 0-4 (low), 5-14 (medium), and 15 or more (high). LOS and cost by annual shoulder arthroplasty hospital volume produced the same strata: 0-3 (low), 4-14 (medium), and 15 or more (high). LOS and cost decreased significantly (P