Public Review: DDI - Cross Domain Integration (DDI-CDI)

The DDI Alliance is pleased to announce the Public Review of DDI - Cross Domain Integration (DDI-CDI), a specification aimed at helping implementers integrate data across domain and institutional boundaries.  The new DDI-CDI is an application of the model which emerged from many years of work on a "next generation" DDI specification, known as "DDI 4."

DDI-CDI focuses on a uniform approach to describing a range of needed data formats (traditional wide/rectangular data, long [event] data, multi-dimensional data, and NoSQL/key-value data) which allows them to be connected and understood to support transformation and processing for integrated use. DDI-CDI is aligned with other DDI specifications (DDI-Codebook, DDI-Lifecycle) to support integration of external data in systems which use DDI. It is explicitly designed to work with many popular generic technology standards such as PROV-O, BPMN, DCAT, SDMX, DataCube, SSN/SOSA and to allow for easy integration into systems which support them.

DDI-CDI offers an extension to the suite of DDI work products which will help those in the SBE domains and outside of them integrate the expanding range of data required by today's research. 

Links to the specification and instructions for comment are found at We are eager to obtain feedback from a broad community on this specification. The comment period is open until July 31, 2020, and we hope to hear from you. To assist you in your review we recommend the following approach: 

Read the Overview section of the DDI-CDI review page. This provides a guide to what you will find in the download package. There are four documents linked from the Overview section. Looking at these in the order presented will provide you with information on the purpose, organization, use, and structure of DDI-CDI. Depending on your areas of interest and expertise, you may be focusing on specific aspects of the package. These documents will help guide you to the relevant material. If you have questions about the package contents and how to review them, use the issue form or email option to ask for clarification. Find these options through the link in the upper right frame of the review page.

Your feedback to DDI-CDI is appreciated.

Update: The DDI Alliance is collaborating with CODATA on a series of webinars to support the public review of DDI-CDI.