This is a historic milestone for data documentation: as of March 6, 2026, the International Organization for Standardization (ISO) has published the ISO/PAS 25955 specification, officially integrating DDI (Data Documentation Initiative) into its standards.
Launched in 1995 at the initiative of the ICPSR, a committee — institutionalized in 2003 as the DDI Alliance (https://ddialliance.org/) — developed this international standard. It facilitates and standardizes the description and documentation of data relevant to the social sciences and economics, gradually incorporating cross-cutting fields such as health and geospatial data.
The Alliance, which includes all major research data banks — most notably the ICPSR and the Data Archives grouped within CESSDA for Europe — now counts numerous national statistical institutes among its members, including Insee (France).
Since the late 1990s, the FPR files, now managed by Quetelet-Progedo, have been documented using DDI. From its inception, the CASD adopted this norm as the standard format for the documentation of data provided by producers. Furthermore, the major Constances epidemiological cohort, whose data is accessible via the CASD, joined the DDI Alliance in 2025.
This major step for DDI crowns the efforts of the DDI Alliance and the IASSIST community toward fine-grained documentation, standardization, and data interoperability.
