By taking the prospective view,
the GGP essentially broadens the explanatory scope of the collected data. To make causal
inferences, the analyst needs data where the hypothesized cause is observed
before the outcome in a person's lifetime. The panel design provides a possibility to use
the broad range of information pertaining to the time of interview in explaining the demographic behaviour
recorded between the panel waves. This is particularly important for variables such as incomes
and opinions that cannot normally be caught retrospectively.
Population scholars increasingly share the view that single-discipline
perspectives for studying population and family behaviour are incapable of producing
major gains in our understanding. The multidisciplinary approach
in the GGP is reflected in the breadth of theories underlying the questions included in the survey
instrument. Among the theories reflected in the questionnaire are the theory of reasoned action,
the theory of the importance of attitudes and norms in social behaviour, theories of the impact
of social networks, and theories of gender and gendered behaviour.
The GGP integrates the broader context within
which people make their behavioural choices into the data design and develops a contextual database.
This is grounded on the assumption that individual behaviour, such as childbearing and
the formation and disruption of co-residential unions, is influenced not only by personal traits, living
conditions, and beliefs, but also by the context within which people live, including their families,
networks, communities, and societies.
From its inception, the GGP has been a joint multi-country research effort. European
countries have many features in common, therefore, it pays for countries to join forces and seek answers
together. The knowledge emanating from a joint effort will better shed light on how each country's
policies actually influence population and family change. In order to enable individual countries to
compare themselves with others as fully as possible, the GGP aims at a high level of
comparability of data and method.
The GGP addresses gender issues throughout its wide range of topics.
It uses stratified nationally representative samples that include approximately equal numbers of
men and women. It collects most of its data from a couple perspective, that is, the respondents
provide a large amount of information also about their current partner if they have one. The
gender issues are taken into account throughout the questionnaire in the formulating the response
items and including thematic blocks of questions. All this allows to study the system of gender
relationships in a country and its link with demographic behaviour.
The GGP covers relationships between generations also
from the viewpoint of the population above the reproductive ages, which allows analysts and policy-makers
to address the pertinent issues of population ageing in developed countries.