Strengths and Limitations
tumor
TUMOR, BLADDER CANCER
The biggest strength of this study is that it was integrated into a high-quality randomized clinical trial with patient-level data for all major cost components and HRQOL. As such, it overcomes the weaknesses identified in a previously published systematic review of robot-assisted radical cystectomy for patients with bladder cancer.The incorporation of patient quality of life into our analysis using QALYs is in line with the recommendation of prominent bodies in Canada, the United Kingdom, and the US.The economic evaluation was also undertaken with direct and indirect stakeholder involvement to ensure its relevance. It was designed with the assistance of the lead clinician of the underlying iROC study, while the final design and conduct of the iROC study was overseen by a steering committee that included patient representatives.The main limitation relating to the clinical evidence is the use of the 90-day follow-up, which is expected to systematically underestimate the HRQOL benefits of iRARC. However, sensitivity analysis explored this, and with extrapolation to what was considered to be the largest plausible length of morbidity benefit (360 days), the ICER remained high. The main limitation for the costs was the lack of study data on the use and cost of instruments for ORC, which meant relying on a previously published figure. While this figure was the most relevant figure available, other available estimates for ORC and related surgical procedures are much lower. This was explored in the sensitivity analysis.The generalizability of costs and cost-effectiveness needs to be considered by funders. While our sensitivity analysis showed that variability in costs has a limited effect, this is based on United Kingdom cost structures and surgical practices. As such, the extent to which these economic results can be generalized beyond the United Kingdom is unknown. Similarly, the funding threshold presented may not be relevant to other countries (even if translated to local currency units). Consequently, local information needs to be taken into account when our results are used to inform policy in other countries. This is perhaps most pertinent to length of stay, as hospitals and/or countries with short lengths of stay may be less likely to be able to deliver the absolute reductions seen here, which will lead to reduced cost-effectiveness.There were 5 deviations from the health economics analysis plan. Three of these relate to the adoption of alternative methods: the choice of hospitals used to estimate costs, the method of extrapolation beyond the trial follow-up, and the source of equipment costs relating to ORC. All changes were explored with sensitivity analysis and were found to alter the results only minimally. The other 2 changes relate to the subgroup analysis of BMI and the exploratory analysis relating to the subgroups analysis of age, tumor size, and performance status. These are clearly reported as post hoc analyses with findings interpreted accordingly.