DDI-Lifecycle (DDI-L)
DDI-Lifecycle Documentation (all versions)
Support for the DDI-Lifecycle from planning through analysis. Organized around major areas of activity: Conceptual Content, Study Unit, Data Collection, Logical Records, Physical Records, Physical Instances (data store), Archiving, Groups, Resources, and Comparison. Introduces the idea of metadata reuse within and between studies, support for repeated surveys, creation and management of questionnaires, and management of metadata over time. Content may be used to populate question, variable, and concept repositories.
DDI-Lifecycle expands on the idea of DDI-Codebook in terms of content coverage, depth, metadata management over time, reusable metadata, and support for the planning, capture, processing, storage, discovery and dissemination of research data. DDI-Lifecycle is the most comprehensive of the DDI products covering conceptual and methodological objects, processing, quantitative and qualitative data objects, and data management. DDI-Lifecycle is appropriate for longitudinal, linked, and other complex datasets.
Supports Activities:
- Descriptive documentation of the content, meaning, provenance, and access for a single data set or series
- Archival preservation of descriptive and production content
- Metadata driven statistical systems
- Input content for discovery and exchange of data at the study, data file, variable, and question level
- Input content for a structured human-readable codebook for the data set as a whole
- Populate variable and question banks to explore available data and question structures for reuse in new surveys
- Metadata reuse for quality control and consistency
- Reuse of metadata within and between studies
- Defining intended processes for data capture, processing, preservation, and access
Management of single or multi-model data capture including generation of data capture forms and instrument content.
Markup Examples
A listing of available examples of DDI-Lifecycle (filter by version is available). Note no markup examples of 3.0 have been made available as it is not implementable.
License
Version 3.2 to date
DDI-Lifecycle XML Schema is free software: you can redistribute it and/or modify it under the terms of the Creative Commons Attribution 4.0 International license.
Other DDI documents are similarly distributed under the same Creative Commons license.
The development of DDI-Lifecycle draws on earlier DDI versions and work of the committees and individuals who developed them as well as the collective ideas, needs, and work of the Expert Committee of the DDI Alliance. Major contributions to DDI-Lifecycle development were made by many individuals and organizations.
Version 3.0 and 3.1
DDI Lifecycle XML Schema is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
DDI Lifecycle 3.0 XML Schema is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
Other DDI documents are distributed under Creative Commons licenses.
Development Work
Development of DDI Lifecycle is managed by the DDI Alliance Technical Committee (TC). The work of the TC can be found at Technical Committee - DDI - Confluence (atlassian.net). Issues related to the general development of DDI Lifecycle are managed at DDI: Lifecycle - Issues - JIRA (atlassian.net). File specific model issues in Development Repository.
Publication date: 2020-04-15
Additions in version 3.3: This version also supports improvements in Classification management (based on GSIM / Neuchatel), non-survey data collection (Measurements), sampling, weighting, questionnaire Design and support for DDI as a Property Graph.
Version 3.2
Publication date: 2014-03-12 Updated: 2024-05-15
NOTICE 2014-05-15: The DDI 3.2 schema package was reissued on 2014-05-15 to correct an error in the HTML version of the Field Level Documentation which resulted in a small number of broken links. No change has been made to the contents of the schemas themselves.
This version of the DDI Lifecycle specification builds on DDI Lifecycle 3.1, correcting documented bugs and refining some aspects of the specification.
Version 3.1
Publication date: 2009-10-15
DDI Lifecycle 3.1 reflects the correction of bugs identified by implementers using DDI 3.0, and the resolution of the final URN structure to ensure persistent URNs for all identified elements. Note that DDI Lifecycle 3.1 is not backward compatible with DDI Lifecycle 3.0. A change file in the download package identifies all changes, including which changes were backward compatible and the steps to take to move DDI Lifecycle 3.0 instances to DDI Lifecycle 3.1.
Version 3.0
Publication date: 2008-04-28
The intent of DDI Lifecycle was to support the management, preservation, and dissemination of complex social science data files. The ability to manage and reuse content improves the ability to capture metadata at its point of origin and then track its use and change over time. The previous version of DDI was DDI-Codebook.