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  • Variations in cost calculations in spine surgery cost effectiveness research

    Final Number:

    Matthew D. Alvin MBA MA; Jacob A. Miller BS; Daniel Lubelski; Benjamin P Rosenbaum MD; Kalil G. Abdullah; Robert G. Whitmore MD; Edward C. Benzel MD; Thomas E. Mroz MD

    Study Design:
    Clinical Trial

    Subject Category:

    Meeting: Congress of Neurological Surgeons 2014 Annual Meeting

    Introduction: Cost effectiveness research in spine surgery has been a prominent focus over the last decade. However, there has yet to be a standardized method developed for calculation of costs in such studies. This lack of a standardized costing methodology may lead to conflicting conclusions on the cost effectiveness of an intervention for a specific diagnosis. The primary objective is to systematically review all cost effectiveness studies published on spine surgery and compare and contrast various costing methodologies used.

    Methods: All cost effectiveness analyses pertaining to spine surgery were identified using the cost-effectiveness analysis (CEA) registry database (Tufts Medical Center, Institute for Clinical Research and Health Policy) and the Medline database. Each article was reviewed for the study subject, methodology, and results. Data were collected from each study, including costs, intervention, cost calculation method, perspective of cost calculation, and definitions of direct and indirect costs if available.

    Results: Thirty-seven cost effectiveness studies on spine surgery were included in the present study. Twenty-seven (73%) of the studies involved the lumbar spine and the remaining ten (27%) involved the cervical spine. Of the 37 studies, 13 (35%) used Medicare reimbursements, 12 (32%) used a case costing database (CCD), 3 (8%) used cost-to-charge ratios (CCRs), 2 (5%) used a combination of Medicare reimbursements and CCRs, 3 (8%) used the National Health Service (NHS) reimbursement system, 2 (5%) used a Dutch reimbursement system, 1 (3%) used the United Kingdom Department of Health data, and 1 (3%) used the Tricare Military Reimbursement system. Nineteen (51%) studies completed their cost analysis from the societal perspective, 11 from the hospital perspective (30%), and 7 (19%) from the payer perspective. Of those studies with a societal perspective, 16 (42%) reported actual indirect costs.

    Conclusions: Changes in cost have a direct impact on the value equation for concluding whether an intervention is cost effective. It is essential to develop a standardized, accurate means of calculating costs. Comparability and transparency are essential such that studies can be compared properly and policy makers can be appropriately informed when making decisions for our healthcare system based on the results of these studies.

    Patient Care: Costs are an important aspect of clinical, insurance coverage, and payment decisions in healthcare. Specifically, cost containment has become a prominent issue in United States (U.S.) healthcare policy. With the continued elevation of healthcare expenditures, medical and surgical interventions are being increasingly scrutinized for their cost effectiveness to both the patient and provider. Given equal effectiveness between two procedures for the same medical or surgical indication, patients, providers, and payers will choose the less expensive procedure. It is the transparency of costs that may benefit both the public and private sectors. A major limitation of existing cost effectiveness studies is the heterogeneous way in which costs are defined and calculated, as there has yet to be a standardized approach for conducting a cost effectiveness study. This limitation leads to great difficulty interpreting the results of CUAs and the potential for biased results. The purpose of this study was to systematically review all cost effectiveness studies in the spine surgery literature, identify how costs were defined and calculated, and compare different cost methodologies among studies analyzing the same intervention. Understanding these differences will aid future investigators in performing more standardized cost effectiveness analyses.

    Learning Objectives: By the conclusion of this session, participants should be able to: 1) Understand how costs are calculated, the terms utilized, and perspective taken in cost effectiveness research and 2) Discuss why it is essential that researchers be transparent about how costs are calculated and from what perspective.

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