What is the difference between Epidemiological Transition Theory and Demographic Transition Theory?”
“The epidemiological transition theory proposed by Omran in 1971 characterizes the historical development of mortality over time in phases of “the age of pestilence and famine, the age of receding pandemics, and the age of degenerative and man-made diseases.” Demographic transition, characterized by a decline first in death rates and then in birth rates, occurred over 100 years in the “Western” model, but happened much more quickly in countries such as Japan (the “accelerated” model). The “delayed” or “contemporary” model is seen in third world countries, where the transition is not complete. The concept of the “Western” model is ill defined and cannot be used without ambiguity because the beginning and end of the epidemiologic transition has not been located in time or clearly defined by Omran. The question remains whether the beginning and end of the epidemiologic transition should be based on trends in all cause mortality or on changes in cause of death patterns. In order for the ep