Introduction: The documented increasing incidence of nephrolithiasis in the United States will likely be associated with significant economic impact. Time-driven activity-based costing is an analytical method that has been successfully adapted from industrial analysis for use in health care. Using this costing approach we characterized the cost of 4 stone treatment modalities at our academic medical center, including trial of passage, semirigid ureteroscopy, flexible ureteroscopy and extracorporeal shock wave lithotripsy.
Methods: We developed process mapping for urological evaluation, treatment and followup of renal or ureteral stones less than 10 mm in size for each treatment method. We calculated cost of resources, equipment, disposables, personnel and space used for each step in the process. Cost was based on the capacity of each resource and the amount of time required for the treatment process.
Results: The cost for trial of stone passage, $389, was expectedly lower than for surgical interventions and was mainly driven by clinic visit costs. Extracorporeal shock wave lithotripsy and semirigid and flexible ureteroscopy costs were $4,367, $4,830 and $5,356, respectively. Intraoperative disposables and personnel were the top contributors to overall treatment costs.
Conclusions: Conservative management is less costly than surgical interventions. Flexible ureteroscopy is the most expensive of surgical interventions. We describe the first time-driven activity-based cost analysis of stone management to our knowledge. Identifying the main drivers of cost can help to improve the value of urological care and improve future cost-effectiveness analyses.
Keywords: costs and cost analysis; health expenditures; nephrolithiasis; urolithiasis.