Data Exchange Tools and Conversion Utilities

This project developed, refined and tested models for data exchange for both survey data and qualitative research data. Research was also conducted into the viability of developing the automated conversion procedures for legacy formats. This has led to the publication of the QuDEx schema, recommended for rich description of archival qualitative data.



project outputs


This project explored the feasibility of developing data exchange models and data conversion tools for primary research data collected in the course of empirical research. It developed, refined and tested models for data exchange for both survey data and qualitative research data based on eXtensible Mark-up Language (XML)/Resource Description Framework (RDF) schema and developed tools for data import and export. The work also researched the feasibility of developing automated conversion procedures for legacy formats.

The data formats included are those that are commonly used in research such as SPSS, Stata, XML, Atlas-ti, MaxQDA and Nvivo. The test data selected for this project were from the social sciences, but these formats were typically found across all domains of primary research. A small scale evaluation of the models and tools were carried out in order to inform Jisc of the most viable options for future development in this area.

The development of a model for describing qualitative data collections took as its starting point earlier work undertaken in the early 2000s by the UK Data Archive on descriptive metadata for its non-numeric data collections.

In 2003 the Archive's qualitative team developed a draft but limited formal definition of a common XML vocabulary and Document Type Definition (DTD) based on the Text Encoding Initiative (TEI) for describing complex data structures. Following a Jisc grant in 2005-2006, a draft XML metadata schema, known as QuDEx (Qualitative Data Exchange) was designed and published. Other existing standards were reviewed as part of this work.

QuDEx arose from a comparison of the key functionalities for the market-leading qualitative software packages in the hope of stimulating data exchange and import and export facilities between these softwares. It defined common denominator functions for documenting,organising and analysing qualitative data: coding, classifying, memoing, and relating. These core concepts helped defined the QuDEx schema.

The QuDEx standard/schema is a software-neutral format for qualitative data that preserves annotations of, and relationships between, data and other related objects. It can be viewed as the optimal baseline data exchange model for the archiving and interchange of data and metadata.

A lay introduction can be found in the 2011 article by Corti and Gregory.

The schema and documentation from the project can be accessed from our metadata standards.

QuDEx Schema



DExT Project Documents

Jisc Bid

Project Plan


May 2008: Final DExT project report to Jisc plus report appendices.

April 2008: The DExT final report from the Quantitative DExT project, undertaken by Pascal Heus of ODaF is now available. The DDI-DExT application is available for download from the project repository on ODaF Forge. Two packages are made available: the main DDI-DExT application and the SPSS Reader. More details on the DDI-DExT application can be found at the DDI Alliance Tools web site.

March 2008: The final schema (version 3) to be created under the DExT Jisc award, associated documentation and XML instance files are all now available from the DExT Schema page.

October 2007: Versions 1 and 2 of the draft QuDex schema were available for comment on the DExT WIKI, now taken down. The previous schema versions plus change notes are available on request.

February 2007: In order to assess the different metadata schemas that are relevant to the description of qualitative data resources, a brief comparison of metadata schemas was produced:

February 2007: A similar comparison has been compiled to compare key CAQDAS functionality that is relevant for any future import and export functionality to a middle-ground non-proprietary format:

Presentations about DExT:

DEXt brochure, 2007

Bhat, A., L'Hours, H. and Corti, L. (2007) Data Exchange and Conversion Utilities and Tools (DExT), presented to meeting of CAQDAS software vendors at the CAQDAS Conference 2007, Egham, Surrey.

At the software vendors meeting an overview of the basic models for data exchange was provided. The software vendors have agreed to discuss which basic aspects of functionality might be common across packages. A WIKI was set up for discussion on this issue.

Bhat, A., Corti, L. and L'Hours, H. (2007) Data Exchange and Conversion Utilities and Tools (DExT), presented at ODaF meeting and ASC Annual Conference, September 2007, St Helens, CA, USA.

Dext team (2007) DExT poster, presented at UK Data Archive 40th Anniversary, October 2007, Colchester, Essex and other ESDS and UK Data Archive events.

Dext team (2007) DExT handout, presented at UK Data Archive 40th Anniversary, October 2007, Colchester, Essex and other ESDS and UK Data Archive events.

Archive contribution

The UK Data Archive researched and developed qualitative and numeric data exchanges and standard conversion tools, which were tested and evaluated.

Principal investigator:  Louise Corti
Funder:  JISC Capital Repositories and Preservation Programme, Tools and Innovation Strand
Dates:  January 2006 - March 2008
Contact:  Louise Corti
Links:  DExT final report
DExT final report appendices
DExT ODAF report
QuDEx schema and documentation