QALYs in cost-effectiveness analysis: an overview for cardiologists.

In recent years, cost-effectiveness data have strongly influenced clinical practice guidelines for several cardiovascular treatments. Economic considerations are increasingly common as health systems are under mounting pressure to maximise value for money. The quality-adjusted life year (QALY)-an outcome measure that expresses the duration and quality of life-is the main pillar of cost-effectiveness analyses. It is widely used in assessments of the clinical and economic value of new cardiovascular treatments, but how the QALY is derived is often unclear to clinicians. In this article, we first explain how QALYs are defined and calculated. We then review a selected set of cost-effectiveness analyses of recently introduced cardiovascular treatments and outline how these studies derived their QALYs. Finally, we discuss the limitations of the QALY and how the presentation of the measure could be improved in cost-effectiveness studies.