In comparative studies, there is a natural trade-off between optimizing cross-countries and optimizing within-countries. In deciding the details of the study's design we have given top priority to the first criterion, i.e. maximal comparability. Strategies were chosen that are feasible and promising in all four national contexts simultaneously. The result are strongly harmonized instruments. Each country team, however, implemented the study in their respective country separately.

The study was originally conducted in:

  • Germany

Kalter, MZES / University of Mannheim
Kogan, MZES / University of Mannheim
Kroneberg, MZES / University of Mannheim (now: University of Cologne)

  • the Netherlands

Kalmijn, Tilburg University (now: University of Amsterdam)
van Tubergen, ICS / ERCOMER / Utrecht University

  • Sweden

Jonsson, SOFI / Stockholm University (now: University of Oxford)

  • England

Heath, University of Oxford
Hewstone, University of Oxford


The German team, under the direction of the project's prinicpal investigator Frank Kalter, was responsible for the international coordination of the project and ensured maximum comparability of the study in terms of questionnaire and sampling. Also, the German team manages the cross-country data sets and their public release.

For more information about the different country teams have a look into our section Team.