The interventions included appeared relevant and the authors seemed to attempt to include the appropriate comparators for their study setting. It was likely that introduction of robotic technology was relevant to other settings and that the comparators reflected generalisable practice.
The focus of the model was costs. There was an assumption of equivalence in surgical outcomes and no consideration of health-related quality of life. This was in part due to a lack of evidence to the contrary and also to enable cost drivers to be determined. The authors discussed the limitations of this approach in full. Operative outcomes were allowed to differ between interventions. Methods for identifying and selecting data were reported in sufficient detail. It appeared that the best available evidence was incorporated in the model. The level of reporting was good. Tables with parameter estimates were presented.
The costs were highly relevant to the stated study perspective and the source of cost data was well described. Methods used to estimate cost data were described adequately in the text. A table of key cost estimates with the range of uncertainty was provided. The authors report neither the price year nor whether they performed other cost adjustment techniques. The generalisability of the costs was likely to be poor.
Analysis and results:
The methods were generally well reported. The time horizon of the analysis was not stated explicitly and this made the results slightly difficult to interpret. The key assumptions of equal outcomes from the alternative surgical techniques needed further validation as the methodological quality of the references supporting these assumptions was unclear. The authors recognised that the impact of different surgical techniques on quality of life was a key omission. The authors conducted one-way sensitivity analysis; more complex multivariate sensitivity analysis would have been a more through method of assessing the joint impact of multiple parameter uncertainty on results. As stated by the authors, the main focus of this paper was costs.
The methodology of the study was adequate. The authors did not make strong recommendations, which was appropriate given the uncertain clinical evidence base.