Interventions:
The reporting was good and the interventions were well described. It appears unlikely that all the relevant comparators were included and, whilst the analysis might reflect the available head-to-head evidence, it was only a partial analysis.
Effectiveness/benefits:
The model used the only available head-to-head data for pregabalin versus lidocaine plasters, and this was a trial, with a good design, which was well described. A Delphi panel, consisting of nine general practitioners was established to produce the estimates for the model parameters, for which no published data were available. This panel improves the reliability of these assumptions. The quality of the available utility data was questionable, but the authors used the Delphi panel to validate these estimates. Despite this, the poor utility data could be considered to be a limitation of the analysis.
Costs:
The costs were relevant to the perspective stated and the study setting, but the long-term costs that might be associated with postherpetic neuralgia, do not appear to have been considered. It is not clear whether this was an influential issue. The Delphi panel appears to have been used to validate and estimate the resource use data. It was appropriate to adjust the costs to a price year, but the use of the health care component of the Consumer Price Index would have been more appropriate as health care inflation often exceeds that of the overall economy. The impact of this on the overall results is likely to have been small.
Analysis and results:
: The analytic approach was described satisfactorily and a diagram of the model structure was provided. The incremental analysis was appropriate to determine the cost-effectiveness of the alternative treatment strategies. The uncertainty in the parameter estimates and model assumptions was appropriately addressed in the sensitivity analysis. The results of the base case and sensitivity analyses were adequately reported. The authors highlighted the strengths and limitations of their study. They appear to have undertaken a thorough and comprehensive analysis, which was enhanced by the appropriate use of a Delphi panel, but limited by the lack of direct evidence and issues with the use of an indirect analysis.
Concluding remarks:
: There were a few limitations to the study, but the methods and results were well presented. The conclusions reflect the scope of the analysis and the evidence available.