Cervical Spondylotic Myelopathy - Cost Observational Surgical Trial
Condition: Cervical Spondylosis With Myelopathy
MeSH terms: Spondylosis; Spinal Cord Diseases; Bone Marrow Diseases
Study type: Observational

Summary: 
      The purpose of the study is to determine the cost-effectiveness of different surgical
      strategies to treat cervical spondylotic myelopathy. The study will use data generated from
      the CSM-S Trial (NCT02076113).

        1. To determine if laminoplasty is more cost-effective compared to dorsal fusion or ventral
           fusion surgery.

        2. To determine the relative cost-effectiveness between anterior cervical discectomy and
           fusion (ACDF), posterior instrumented cervical fusion (PCF), and cervical laminoplasty.
    

Detailed description: 
      In this study, the investigators aim to cover a significant gap in the literature, namely, to
      compare anterior and posterior surgical approaches for the management of CSM on the cost of
      care. The investigators will conduct a post-hoc analysis of data from the randomized trial
      "Cervical Spondylotic Myelopathy Surgical Trial" (www.ClinicalTrials.gov; identifier:
      NCT02076113). This trial was conducted in collaboration between multiple academic
      institutions in North America. The results of the CSM-S RCT in terms of clinical and
      patient-reported outcomes suggested similar effectiveness with anterior and posterior
      surgical approaches. Notably, the study showed that cervical laminoplasty, a relatively low
      instrumentation-related cost procedure, was effective in managing CSM. The findings of the
      analysis proposed herein will add a new dimension to clinical decision-making by informing
      patient selection and improving the quality of care.

      Post-hoc analysis will be conducted on the following data that were collected during the
      trial.

      I. Functional outcomes determined by well-known quantitative scales (SF-36, Oswestry Neck,
      mJOA, and EuroQol-5D) at pre-op, 3 months, 6 months, 1 year, 2 years, 3 years, 4 years, and 5
      years.

      II. Health resource utilization information was collected using patient diaries along with
      copies of all medical bills and receipts at 1 month, 3 months, 6 months, and 12 months
      post-operatively for all patients. Participants were asked to monitor days missed from work
      and days unable to perform usual activities, in addition to days missed from work for medical
      treatments or evaluations.

      The overall cost will be estimated for each patient from a societal perspective and will
      include the following components:

      I. Index Hospitalization Cost - performed on all patients:

        -  Hospital Costs: Total hospital charges (TotalHC) will be used to estimate costs using
           hospital-specific and year-specific Medicare cost-to-charge ratios (CCR). The costs will
           be adjusted for inflation to the latest year of the study (2018) without a 3% discount.
           - Assumptions: cost-to-charge ratios for all hospitals and all relevant years will be
           provided. Data will be complete for all patients from all sites.

           o As a sub-analysis, hospital charges for specific revenue centers (i.e., radiology,
           pharmacy, physiotherapy, and occupational therapy) will be converted to costs using
           hospital-specific and year-specific CCRs. This will allow the identification of the
           major drivers of the difference in cost between the surgical strategies. A crosswalk
           between the revenue center and the cost center will have to be created. - Assumptions:
           Total hospital charges will be segmented out into the relevant revenue centers. All
           patients will have charges segmented in this manner. No major differences in how total
           hospital charges will be segmented by each site will exist.

        -  For professional services (identified with either HCPCS code or CPT-4 codes) provided to
           patients during the index hospitalization, costs will be calculated using national
           reimbursement amounts from the appropriate Medicare fee schedules for the respective
           year. - Assumptions: Detailed line-item services of all HCPCS codes and CPT-4 codes
           (including any necessary billing modifiers) will be provided for all professional
           services. Data will be complete for all patients from all sites.

      II. One-year All-Cause Cost - performed on patients from sites capturing 1 year utilization:

      • One-year all-cause costs will be calculated on hospital and professional services in the
      manner described above. - Assumptions: The same underlying assumptions described above.

      III. Time to Return to Work - performed on all patients reporting employment:

        -  Investigators will assume that the work halted for patients on the procedure date).

        -  For patients to whom this outcome applies, the investigators will compare different
           cohorts using return to work as a time-to-event outcome.

        -  Lost wages will be estimated using the median weekly earnings in the US as reported by
           the Bureau of Labor Statistics.

        -  Patients providing no employment information will be assumed to have zero lost wages.

        -  Job-specific wages will not be estimated.

      Index hospitalization costs and one-year all-cause costs will be combined with costs due to
      loss of productivity (indirect costs) to estimate total costs for each patient from a
      societal perspective. This will be performed on the subpopulation for which one-year costs
      were captured.
    

Intervention name(s): ACDF; Posterior Cervical Fusion; Cervical Laminoplasty
Intervention type(s): Procedure; Procedure; Procedure
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Study population consists of patients with multi-level cervical spondylotic myelopathy
        without kyphosis and who satisfied clinical equipoise criteria (ventral vs. dorsal
        approach) as judged by a panel of at least 15 spine experts.
      
Keywords: cost-effectiveness; cervical spondylotic myelopathy; health resource utilization; spinal fusion; laminoplasty