The disability-adjusted life year (DALY) definition, measurement and potential use

The 1993 World Development Report (WDR), Investing in Health, used the Disability Adjusted Life Year (DALY) to measure the state of health of a population and, together with the concept of cost-effectiveness, to judge which interventions to improve health deserve the highest priority for action. The DALY is the only quantitative indicator of burden of disease that reflects the total amount of healthy life lost to all causes, whether from premature mortality or from some degree of disability during a period of time. This paper describes the methodology used in the WDR to calculate DALYs and how they can be used for setting health service priorities.