Cost-effectiveness In economics, comparison of the relative expenditure (costs) and outcomes (effects) associated with two or more courses of action. Cost-effectiveness is typically expressed as an incremental cost-effectiveness ratio (ICER) the ratio of change in costs : change in effects. In health economics a figure of US$50000 per quality-adjusted life year (QALY) is often suggested as the upper limit of an acceptable ICER. There is lively discussion amongst Health Economists as to the meaning and usefulness of such a figure.