ABSTRACT
This chapter aims to look in detail at some of the more important examples of longitudinal studies and, at the same time, examine the crucial issue of comparability in dynamic research. Currently, many independent national longitudinal studies are in operation in different countries of Europe and in North America. Although the contents of the questionnaires used may vary, in order to reflect the particular research purposes and policy interests of their sponsors, data are routinely collected (prospectively or retrospectively) on matters such as employment, family structure and changes in income, housing, consumption and health.
