The level of reporting of the interventions and the treatment pathway was good. The two alternatives included in the analysis appeared relevant to the study setting. The authors justified their choice of comparators on the basis of market share (candesartan) and expected efficacy (olmesartan). Five other available comparators were excluded and readers should consider whether this was appropriate or might have affected the validity of the analysis.
Despite its reliance on effectiveness data the analysis was presented with a cost focus. Hence, the level of reporting around the effectiveness data was poor. The authors did not describe the process of identifying and selecting studies from the published literature so it was unclear whether the best available evidence was incorporated into the model. The estimates used were presented in a table. Specific estimates were not linked to references. The authors did not report full details of the methods used to make indirect comparisons.
The costs included were relevant to the stated perspective. Additional costs (such as those related to the consequences of high blood pressure) could have been included and these costs would also fall on the NHS. The sources of cost data were well described. The short-time horizon of the model made it appropriate for the authors not to discount future costs. Readers should consider whether a one year time horizon was sufficient to fully capture relevant differences.
Analysis and results:
The model structure was presented in full detail. An incremental analysis was appropriately conducted to assess the relative cost-effectiveness of two treatment alternatives. The results were reported in adequate detail. The authors did not appear to fully address the impact of uncertainty; the level of reporting of the threshold analysis was adequate but this type of analysis alone may have been insufficient. The authors highlighted some of the limitations of their study.
The authors’ conclusions should be considered with a degree of caution.