This economic evaluation was based on a probabilistic Markov model that simulated the management of the eligible population and the risk of IHD (myocardial infarction and death). A lifetime horizon (60 years) was adopted. The authors stated that the perspective of the payer was adopted.
The clinical data were derived from multiple sources, which appear to have been identified selectively. Treatment effectiveness was based on head-to-head trials in which ROS was directly compared with another statin. Basically, pooled data from 5 double-blind, randomised, clinical trials (RCTs) were used for the first 12 weeks of treatment. Longer-term data on pravastatin and simvastatin were derived from a single open-label RCT; data on atorvastatin and rosuvastatin were based on a randomized double-blind clinical trial. The impact of LDL levels on IHD events was based on a meta-analysis of 58 selected RCTs. Epidemiological data (mortality rates, life-expectancy and incidence of myocardial infarction) came from Portuguese sources.
Monetary benefit and utility valuations:
Measure of benefit:
The summary benefit measure was survival (i.e. life-years, LYs). The LYs were estimated using the decision model. An annual discount rate of 5% was applied.
The health services included in the analysis were statins and treatment of a nonfatal myocardial infarction. The latter category consisted of the diagnosis-related group price for hospital services plus the cost of ambulatory care. The unit costs were based on official Portuguese sources. Resource consumption was based on the estimation of a Delphi panel of 8 Portuguese cardiologists with at least 15 years of clinical practice. The price year was not explicitly reported. The costs were in euros (EUR) and were discounted at an annual rate of 5%.
Analysis of uncertainty:
The uncertainty in input parameters was addressed by means of 10,000 Monte Carlo simulations. All model inputs, except the price of statins, were assigned specific probabilistic distributions. These were described clearly.