Background: Increasing attention is being focused on the costs of healthcare and the need for cost-effective treatments. Drugs for schizophrenia have not escaped this scrutiny, especially now that several new agents are available, with acquisition costs substantially higher than for established therapies. However, most of the existing evaluations of new drugs for schizophrenia have weak designs, either comparing health care costs before and after introduction of the new drug, or being based on modelling approaches incorporating numerous assumptions.
Aim of the Study:
The aim of the study was to discuss and resolve the key design issues in the planning of a prospective randomized trial to assess the socio-economic impact of a new atypical antipsychotic (quetiapine). Methods: Key methodological issues were identified and discussed in the context of the economic evaluation being planned. These were patient recruitment and entry criteria, selection of comparator drug, blinding of doctor and patient, range of socio-economic outcomes, length of follow-up and sample size.
Results:
The resulting economic evaluation, the ESTO study, was an international multi-centre randomized controlled trial, with concurrent data collection for a wide range of clinical, economic and quality of life outcomes. The trial had a pragmatic design, enrolling patients experiencing an acute exacerbation on existing therapy. In addition to the presenting exacerbation, patients must have had at least one hospitalization or documented evidence of exacerbation within the previous three years. On admission to the study, existing psychotic medication was withdrawn prior to randomization to quetiapine or haloperidol. Doses of both drugs were titrated up to an optional dose, with flexibility for additional increases if required.
Both patients and doctors were blinded to treatment allocations, on the grounds that, since quetiapine was still in development, unblinded assessments of efficacy would not be credible. Patients were followed for 1 year, irrespective of whether they withdrew from study medication.
A wide range of socio-economic outcomes was assessed, including costs falling on the healthcare sector, other agencies and the family. In addition data were collected on patients' earnings and quality of life, measured by the Short-Form 36 health profile. Data were also collected on a range of clinical measures, such as