Interventions:
The interventions were clearly reported and the usual care was appropriately included.
Effectiveness/benefits:
The authors reported that the clinical and effectiveness measures were from studies identified through MEDLINE searches. It appears that a full systematic review of the literature was not conducted and it is not possible to determine if all the relevant information was included. The objective was to assess the effectiveness required for genotyping to be cost-effective, given the various effectiveness estimates reported in the literature, and this was appropriate.
Costs:
The authors reported that a societal perspective was adopted, but indirect costs, such as productivity costs due to early mortality or morbidity, were not included. All the direct medical costs appear to have been analysed and their sources were adequately reported. The time horizon, price year, inflation indices, and currency details were all adequately reported, but the discount rate was not.
Analysis and results:
All the outcome and cost data were synthesised using a decision analytic Markov model. Adequate details of the model were provided, including a diagram. The costs and benefits of the genotyping strategies were not reported. The impact of uncertainty on the model’s results was assessed using probabilistic sensitivity analyses. This type of analysis is considered to be the gold-standard in the UK for assessing the overall model uncertainty. The authors adequately reported the limitations of their study, namely that the long-term data were not available and had to be extrapolated.
Concluding remarks:
The methods were good and, given the poor quality or lack of effectiveness data, the authors’ conservative conclusions appear to be warranted.