Component-Level Cost and Variability Drivers of Intradetrusor OnabotulinumtoxinA Injections Across Office and Operating Room Settings

PURPOSE: To identify component-level drivers of cost variability for intradetrusor onabotulinumtoxinA (BTX-A) injections for overactive bladder across office-based clinic, tertiary operating room (OR), and hospital outpatient department (HOPD) settings. METHODS: We performed a retrospective cost analysis of BTX-A injection encounters from January 2020 to June 2025 using institutional activity-based cost accounting data. Costs were grouped into procedural components and categorized as direct or indirect. Mean costs were compared using Welch's t-tests with Bonferroni correction. Utilization-adjusted variance decomposition identified component-level drivers of cost variability. RESULTS: The cohort included 322 tertiary OR, 125 HOPD, and 1,492 clinic encounters. Mean total costs were $4,633.87 in the tertiary OR, $5,063.32 in the HOPD, and $1,899.01 in clinic. Total cost variability differed by setting. In the tertiary OR, variability was driven by supplies (29.5%), OR time (25.7%), and post-anesthesia recovery (25.5%), while direct cost variability was dominated by supplies (45.1%) and indirect variability by OR time (56.0%). In the HOPD, total cost variability was driven by OR time (41.2%), anesthesia (29.2%), and recovery (16.1%), with similar drivers of indirect variability. In clinic, total and direct cost variability were driven primarily by cystoscopy (63.9% and 68.7%) and BTX-A (36.1% and 31.3%), while indirect variability was driven by BTX-A (65.4%). CONCLUSIONS: Cost variability differs substantially across procedural settings. Cost-containment efforts should target setting-specific variance drivers rather than mean costs or site of service alone.