Health Research

"If one views a death from the standpoint of its effect on a population, to count it as an occurrence is insufficient. Its real effect is that of removing a definite number of man-years from the population over a predictable span of time. Therefore, the lost man-years or ‘years of life lost’ due to a specific class of disease should also be a consideration in assigning priorities" (Miller, 1970).

Source: Health Research, HR4D-net group;
http://www.pitt.edu/~super1/lecture/lec14691/006.htm