Analytical approach:
The analysis was based on a decision-tree model, with a 12-week time horizon. The author stated that it was carried out from the perspective of the public payer.
Effectiveness data:
The clinical data were from two trials that were part of the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study. One trial studied the switching option, compared with other treatments, and the other studied the combination option. The key clinical inputs were the remission rates, rates of non-remission, discontinuation rates due to intolerance, and incidence of serious adverse events. These data were from the two trials.
Monetary benefit and utility valuations:
The utility values were based on a published report that used the standard gamble technique and the Short Form (SF) 36 Health Survey in patients with major depressive disorder.
Measure of benefit:
Quality-adjusted life-years (QALYs) and remission rates were the summary benefit measures. Remission was defined as a total score of seven or less on the 17-item Hamilton Rating Scale for Depression (HRSD-17) after 12 weeks of treatment.
Cost data:
The economic analysis included the costs of drugs, hospitalisation, and electroconvulsive therapy (ECT). Most of the resource quantities were from the two clinical trials. The unit costs were from official Thai sources and from a Thai government-run hospital. All costs were in Thai baht (THB) and the price year was 2009.
Analysis of uncertainty:
One-way sensitivity analyses and threshold analyses were carried out on the most influential inputs, which were the probability of remission, the duration of treatment, and the cost of citalopram.