The GGS survey in Belgium

The basis for the Generations and Gender Programme is the Generations and Gender Survey, a large-scale survey on several social demographic issues

The surveyed population

The survey is designed as a longitudinal survey with at least three data collection waves and a 3-year interval between waves. The same group of individuals is interviewed at each wave. The population is defined as the non-institutionalized population aged 18-79 at wave 1. The selection of the non-institutionalized population excludes people who live in an institution, in a home for the elderly or a nursing home, in prison… from the first survey. Those people are taken into consideration for the follow-up surveys. The total Belgian population amounted to 10,666,866 persons (source: STATBEL) when the sample was drawn (1 January 2008). The survey population amounted to 7,828,470 persons at that moment. This is 73% of the total Belgian population at that moment.

 

Representativeness of the data

It is of crucial importance for both basic scientific research and policy support studies that the results of the analyses carried with GGS data are representative of the whole population. Representativeness can be achieved in two ways. On the one hand, the sampling is designed as a classical random sample, i.e. a stratified two-stage sample using the National Register as basis. 17,836 people in total were selected this way. On the other hand, after having collected the GGS data, we thoroughly analysed the non-response (at interview as well as at item level) and corrected it through weighting factors when necessary.

The questionnaire

The purpose of the Generations and Gender Survey is to collect internationally comparable data in the participating countries. Therefore, the United Nations developed an international standardized questionnaire, called the wave 1 core questionnaire. The basic principle is that all participating countries implement as much as possible this core questionnaire in their own questionnaire. The Belgian questionnaire is made up of a contact sheet and 12 thematic modules. The 12 modules are based to a large extent on the questions from the core questionnaire, with some modifications and additions. The Belgian questionnaire includes a contact sheet while the core questionnaire does not. The information of the contact sheet allowed us to closely monitor the fieldwork and to analyze the response in great detail.

 

Modules of the Belgian GGS Questionnaire:

 

The full questionnaire used for wave 1 in Belgium can be downloaded (FR/NL) .

Fieldwork

The fieldwork of wave 1 of the Belgian GGS took place between February 2008 and May 2010. The fieldwork has been closely monitored in order to maximize efficiency of the data collection and quality of the collected data. Interviews were taken at the respondent’s home through face-to-face interviews (CAPI). We obtained 7,163 complete interviews in total. A first analysis of the results shows that they are highly reliable and that most respondents’ were willing to participate. Almost all respondents declared that they were willing to participate to the follow-up survey.