Methods and sample – Survey 1990
The 1990-questionnaire was designed by the Steering Committee in close consultation with national research teams and representatives of fieldwork agencies. In 1989 the questionnaire was first piloted in Great Britain, Spain, Germany, France, and the US. The results were discussed in the Steering Committee. After this, the final 1990-questionnaire was produced in English language and translated in the national languages.
In all countries, the same questionnaire was administered to respondents in personal interviews. Surveys were conducted by national fieldwork agencies. National samples were drawn from the population of adult citizens over 18 years of age. In some countries, random sampling was applied, in others quota sampling. The samples were weighted to correct for gender and age. The Italian 1990 sample was weighted additionally to correct for the level of education. More information on the 1990 survey and a comparison with the 1981 survey can be found here.
Overview and comparison of variables
During the period in which the four surveys were held, the format and contents of the surveys have changed. Variable names are different between surveys, questions have been removed or adjusted, and new topics have been added. Here you can view variables that are included in the 1981-, 1990-, 1999- and 2008-data files. This document (PDF, Excel) gives an overview of the existing variables, and it also shows which of the variables in the four surveys are comparable over time.
Access to data and documentation
Data and Documentation: Information about and access to the integrated dataset and documentation.
Participating countries and country-information: Information about national datasets and access to field questionnaires.