The selection of comparators was appropriate because the proposed intervention was compared against the conventional approach before the implementation of the ERAS protocol.
Use of a historical and retrospective control group identified in a previous time period to that of the intervention group was the main limitation of the analysis. The authors stated that the two groups of patients were well matched at baseline but the lack of simultaneous assessment and the potential impact of time-related confounding factors might have affected the validity of the clinical comparison, so changes in factors other than the study intervention might have had an impact on the clinical outcomes. No power calculations were performed to show the appropriateness of the sample size. Evidence came from a single institution that might not be generalisable to other health care centres. No summary benefit measure was used as a cost-consequences analysis was performed. Several clinical endpoints were used but all of them represented intermediate measures of the impact of the programme on patient health.
The perspective of the analysis was that of the health care provider and this was reflected by the included cost categories. A clear breakdown of cost items was reported and unit costs were presented separately from resource quantities which increased the transparency of the economic analysis. Resource use data were collected from patients included in the clinical study and reflected the authors’ institution. Costs were not varied in the sensitivity analysis and were treated deterministically. The price year was not reported and reflation analysis would not be possible. Discounting was not necessary given the short time horizon of the analysis.
Analysis and results:
The study results were presented clearly. There was no synthesis of costs and benefits as the authors carried out a cost-consequences analysis. The issue of uncertainty was not investigated and the external validity of the study appeared low. The authors acknowledged some limitations of their analysis mostly related to the design of the clinical analysis. Study findings should be considered specific to the authors’ setting and not transferable to other jurisdictions. The authors stated that very few economic analyses on ERAS had been published at the time of their study.
The analysis has some potential methodological limitations and did not consider the issue of uncertainty so caution is required when interpreting the conclusions.