A cohort effect is generally defined as a group of people who have lived through a certain period of time and shared common historical experiences. It is used in particular of people born in the same year. It is thought that cohorts born several decades apart, for instance, may be affected in systematically different ways by the different zeitgeist and social/environmental conditions of their times. An analysis of the cohort effect gives greater depth and complexity to the information provided by both cross sectional and longitudinal research.
Definition