DALYS are the way that statisticians attempt to measure the suffering caused by an illness. Disability Adjusted Life Years (DALYs) take into account both the years of potential life lost (YPLL) due to premature mortality as well as the years lost due to disability due to a disease or health condition. One DALY represents the equivalent of the loss of one year of full health.

The disability-adjusted life year (DALY) is a measure of overall disease burden, expressed as the number of years lost due to ill-health, disability or early death