Death Rates: A cautionary note from 1937
The crude death rate, for well known reasons, is not a good measure, because it is quite seriously affected by differences in age composition. Standardized death rates, on the other hand, have the disadvantage that they depend on an arbitrarily selected standard population.
–Dublin, L.I. and Lotka, A.J. “Use of the Life Table in Vital Statistics.” American Journal of Public Health. Vol. 27, May, 1937.