The DDI Metadata Standard (Data Documentation Initiative) has been used in the GESIS Data Archive for survey documentation and archiving since it was developed. The approach of the recent version of DDI, DDI-Lifecycle, is that this structured metadata allows for re-using it in all stages of the data life cycle: research, study planning, data collection, data analysis, as well as archiving and registering. Thus, the Data Archive has defined a specific workflow and several tools for it to accomplish that. This workflow will be demonstrated with the example of the European Values Study (EVS).
The EVS is a four wave comparative survey with now 47 participating countries/regions. It provides insights into the ideas, beliefs, preferences, attitudes, and values of citizens all over Europe. The waves took place in 1981, 1990, 1999, and 2008. The documentation is related to the national, integrated, and longitudinal datasets and covers altogether 125 national surveys. It contains beside methodological information the documentation of variables with English master questions and partly original questions. A detailed description of the project and data management is provided as well. The close collaboration between the EVS groups at Tilburg University, EVS member countries, survey organizations, and the GESIS Data Archive allowed from the beginning considerations on which kind of metadata should be produced and be covered by review procedures.
For the EVS, users can check the translations of the English master questions, compare original questions across languages, countries, or waves, detect problems or peculiarities, and report on the findings. This is supported by tools like ZACAT, the Data Archive’s online tool for retrieval, analysis and downloads for datasets, and the Online Variable Overview, a web page for retrieval and comparison of variable documentation. The Section “Errata and Version” in the study description of the GESIS Data Catalogue provides all errata detected in the data. The EVS Repository provides bibliographic information on publications based on EVS data, and it contains publications enhanced by information on how the theoretical concepts have been measured and links to the dataset version and variables used.

The long-term character of the EVS project allows building on experiences of previous waves. Beyond that, it requires keeping the coming EVS waves in mind with regard to collecting and preserving all key data and information. By supplying the scientific community with this structured metadata, the re-use of the documentation is stimulated for both secondary analysis and new research projects.