Both interventions were well described. The authors reported that, at present, infliximab dose escalation is used in patients who have lost response to the standard dose.
The effectiveness data were derived from several published studies. The authors did not provide any information or details of these studies. However, they did provide the relevant references. The methods used in the literature review were not reported. Therefore it is not possible to ascertain if the best available evidence was used in the model. Appropriate details of the sources and methods used to derive utility estimates were given. The reader should consider if a time horizon of 1 year is adequate to capture the differences in health outcome.
The authors did not report the study perspective. However, all costs relevant to the perspective of a health care system appear to have been included. The resource use data were derived from those studies used to derive the effectiveness data. The authors reported the unit costs used and their sources. The price year was reported, as were the methods used to adjust costs to a base year. However, adjusting costs using the health care component of the CPI would have been more appropriate than using the overall CPI, as health care price inflation is generally higher than that for the overall economy.
Analysis and results:
Overall, the analytical approach was satisfactorily reported, with the model structure being reported in full and a graphical depiction presented. The results were also reported clearly and in full. Appropriate one- and two-way sensitivity analyses were performed and reported. Although these types of sensitivity analyses go some way towards addressing parameter uncertainty, the use of a probabilistic sensitivity analysis would have been a more thorough way to fully capture parameter uncertainty. Overall, the level of reporting was good with the base-case estimates of the effectiveness, utility and cost data being reported. In addition, the authors acknowledged and highlighted the limitations of their study.
Overall, the quality of the methodology and reporting of results were satisfactory. However, given their findings, the authors should have clearly reported in their conclusions that infliximab dose escalation was not cost-effective.