Data Documentation Initiative (DDI) Lifecycle (DDI-Lifecycle, DDI-L) is designed to document and manage data across the entire life cycle, from conceptualization to data publication, analysis and beyond. The freely available international DDI standards describe data that result from observational methods in the social, behavioral, economic, and health sciences. DDI is used to document data in over 80 countries of the world. It encompasses all of the DDI-Codebook specification and extends it. Based on XML Schemas, DDI-Lifecycle is modular and extensible.
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