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DDI metadata standard

The Data Documentation Initiative (DDI) is an international metadata standard designed to describe socioeconomic surveys, censuses, and other microdata collection activities. The DDI standard is developed and maintained by the DDI Alliance, and the IHSN is an active partner in its development. Based on feedback from agencies in low- and middle-income countries who are using DDI-based IHSN tools, and from regional and international agencies such as the World Bank, the IHSN requested an upgrade of the DDI specification, which led to the release of version 2.5 of the DDI Codebook standard. The IHSN also works with the DDI Alliance on the certification of the DDI Codebook as an ISO standard. In addition, the IHSN commissioned the production of a paper describing various metadata standards relevant for microdata management.

Project status: Open
Sponsor(s): World Bank Development Grant Facility, Grant No 4001010-06, administered by the PARIS21 Secretariat at OECD
Implemented by: DDI Alliance and IHSN consultants
Type of output: International XML metadata standard and technical note on metadata standards

The DDI Alliance, hosted by the University of Michigan, maintains the DDI metadata standard. Its website provides detailed information on the DDI Codebook and DDI Lifecycle specifications, and provides a catalog of tools that make use of the DDI standard.


These technical notes describe the various metadata standards relevant for statistical data, especially microdata, documentation.


For more information on the DDI and other metadata standards, see our Guidelines on Metadata Standards.

The IHSN also supports the development of a DDI Metadata Editor and other DDI-compliant tools; see our Software section.