Critical analysis of the applicability of the Gompertz-Makeham law in human populations.

The adequacy of the Gompertz-Makeham law (Rt = Beat + A) for a description of human mortality was tested. The analysis was based on statistical data of current mortality rates in men and women of 35 countries for 5 calender years. The study tested the justification of the part of the Gompertz-Makeham law postulating that age-associated mortality (i.e. Beat) increases exponentially. It was found that the alpha parameter of the age component of the Gompertz-Makeham law was not a constant value within the age range 35-75 years, but had rather an age-associated shift which was qualitatively different in men and women. The conclusion was made that the Gompertz-Makeham law did not adequately describe the mortality pattern of a modern human population. This should be borne in mind when use is made of mortality indices for the analysis of the human aging process.