Lecturer
Vladimir Canudas-Romo,Assistant Professor, John Hopkins Bloomberg School of Public Health.
Summary
The great shift in causes of mortality and morbidity that occurred in the developed world predominantly during the twentieth century is recognized in the framework of the demographic and epidemiologic transitions. Today’s industrialized countries have largely progressed through both transitions, as observed in the uninterrupted long historical rise in life expectancy at birth. This paper discusses the methodology to study the cause-contribution of specific causes of death to the change in measures of longevity: The mean and modal ages at death. Methods to assess the cause, decomposition of the change in life expectancy, or mean age at death, are widely used by demographers.
Less attention has been put to study methods of cause-contribution to the change in modal age at death, or age with the highest probability of dying. The main aim of this paper is to present a new proposal of cause-decomposition to the change in modal age at death. This decomposition is based on the recent finding that for the modal age at death to change to older ages it is required that the decline in mortality occurs at ages older than the modal age at death. The method follows two simple steps: (i) to identify modal ages at two given years M(t1) and M(t2), foryears t1 and t2 respectively; (ii) For each year t1 and t2 the cause of death distribution after the modal ages is used to apply the statistical calculations of composition analysis of causes of death. This method allows studying the cause of death change that went along the decline in death rates and which triggered the increase in the modal age at death.
