Marten J. Poley - Erasmus Universiteit Rotterdam

142GlossaryCharge (or: tariff)A price imposed on health care goods or services. Economicevaluations often use charges (set by the market place or byregulation) as a proxy for costs. Yet, charges may bear littleresemblance to real economic costs.ComparatorThe intervention against which the intervention under appraisal iscompared. The comparator can be existing clinical practice or 'notreatment', for example.Cost-effectiveness analysisA term often applied to a specific type of economic evaluation inwhich consequences of different interventions are measured usinga single outcome, usually in 'natural' units (e.g., reduction ofblood pressure, heart attacks avoided, life-years gained, deathsavoided). In this thesis however, it is used as a synonym foreconomic evaluation. See 'Economic evaluation'.Cost-effectiveness ratioThe main outcome measure of economic evaluations—expressedas monetary cost per unit of outcome, such as cost per life saved,cost per QALY, or cost per life-year—used to assist incomparisons among programs. The cost-effectiveness ratio iscalculated as the difference in the costs of the intervention underappraisal and the costs of the comparator, divided by thedifference in the effects.Cost-effectiveness thresholdA certain cost-effectiveness ratio (such as cost per QALY of$ 30,000) against which evidence from economic evaluations iscompared. Decision makers will use the 'threshold' costeffectivenessratio to make judgments about the costeffectivenessof health technologies. If a technology's costeffectivenessis below the cost-effectiveness threshold, itsprobability of acceptance increases.Cost per life saved (or: cost per additional survivor)An example of a cost-effectiveness ratio. See 'Cost-effectivenessratio'.Cost per life-year (gained)An example of a cost-effectiveness ratio. See 'Cost-effectivenessratio'.