Scarcity of resources means that difficult choices have to be made about to use them. Cost-effectiveness evidence provides a way to help decision-makers get ‘best value’ from their resources when choosing between two or more clinical or other interventions. Often it is found that one intervention has better outcomes than another, but also costs more. In these circumstances there is a need for the decision-maker to reach a view as to whether those better outcomes are ‘worth’ the higher costs, necessitating difficult trade-offs. Illustrations from the dementia field are given to illustrate how these trade-offs might be made. For strategic decisions it has often proved helpful to use a generic outcome measure such as the quality-adjusted life year (QALY). The fundamental aim of a healthcare system is not to save money, but to save and improve lives. Cost-effectiveness and similar analyses can help by showing how to get the most out of available resources.
