Disability-adjusted life year

DALY is used interchangeably with DALYs: Disability-adjusted life years

One DALY can be thought of as one lost year of "healthy" life. The sum of these DALYs across the population, or the burden of disease, can be thought of as a measurement of the gap between current health status and an ideal health situation where the entire population lives to an advanced age, free of disease and disability.[1]

Specifically, DALY is the sum of years of potential life lost due to premature mortality (YLL) and the years of productive life lost due to disability (YLD), i.e. $DALY = YLL + YLD$.


Thus, for example a high number of DALYs per 100.000 population implies a high burden of disease in that population.

See for example the ranking of countries by DALY (figure) comparing francophone vs non-francophone African countries, published in The Lancet Global Health (2020).[2]

See also: QALY