Cost-effectiveness comparisons using "real world" randomized trials: the case of new antidepressant drugs

While randomized clinical trials remain the "gold standard" for comparisons of treatment efficacy, conventional randomized trials may not reflect the relative effectiveness of treatments under "real world" conditions. Observational data more closely reflect the conditions of actual practice, but are often limited in clinical detail and subject to bias in selection of treatments. The authors use available data on the cost-effectiveness of new antidepressant drugs to illustrate the limitations of these methods. Modifications to the traditional randomized trial may allow more accurate assessment of effectiveness in everyday practice. The authors describe the design of such a "real world" randomized trial comparing newer antidepressants with older alternatives.