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DCMI Usage Board - Meeting Agenda

Guidelines for reviewing and acknowledging vocabulary and encoding scheme qualifiers

Material for discussion

  • DCMI does not approve vocabulary and encoding schemes, but acknowledges formally maintained schemes as suitable for use with DC metadata.

  • A registry of vocabulary and encoding schemes might be established and maintained by others (metadata registries; cf. the NKOS effort at The information DCMI needs fits in the proposed NKOS scheme.)

  • DCMI should try to agree with future maintainers of a vocabulary registry on data elements and definitions which guarantee that DCMI and metadata design needs are fulfilled. Vocabularies and encoding schemes registred there (if necessary with a specific indicator) would be "automatically" acknowledged for use in DC metadata.

  • In the meantime DCMI needs to establish a public list of acknowledged schemes. It might be appropriate to maintain separate lists for vocabulary qualifiers to the Subject element and for encoding schemes for use in the other elements. The Usage board creates the list proactively and adds to it on request. Relevant parts of the MARC code lists and schemes used in known metadata implementations are used to build an initial version. The public list page features a submission form where everyone can ask for acknowledgment of a scheme.

  • For each scheme the list should provide the following information:

    • Name of the scheme
    • Label/acronym
    • URL for online access (if applicable)
    • URL (or physical address) to access information

Ex.: Dewey Decimal Classification | DDC | Web Dewey in CORC | |

Ex.: Getty Thesaurus of Geographic Names | TGN | | - |

  • Rules about what kind of schemes will be acknowledged

    • Schemes created and maintained by trusted authorities and properly published are acknowledged and listed.
    • Only schemes with a decently sized user base at national or broader level should be listed
    • The DC qualifier document and user guidelines should state, that the listed qualifiers are only appropiate for an unchanged use of an official version of the scheme. Unofficial versions, modified versions, unofficial translations and similar should not use the official label but apply a local name (e.g. service, project or provider name. Ex.: DutchESS or DutchESS-BC if it is really close).
    • An unaltered subset of an official scheme does not need to be indicated or named differently.
  • Rules about the naming of the schemes

    • Schemes should be named with their official names
  • Rules about the acronyms used as DCMI qualifier labels (?)

    • Existing official acronyms or short names should be used as labels.
    • In case communication with the scheme owner does not result in an agreed label, the Usage Board creates and lists a suitable label.
    • Official translated versions receive a label where a standard language code is added, e.g. DDC-fr. This is necessary since translated versions are rarely fully equivalent.
  • Rules about the specification of scheme versions

    • The DCMI list does not register versions of the schemes
    • Users should be encouraged to indicate the official version of the scheme used, e.g. DDC21, DDC21ab-fr, MSC2000
  • The Usage board acknowledges schemes after applying above rules by including them into the public list. That is the confirmation that they are appropriate for use in DC metadata.

Related links:
Draft list of candidate vocabularies

MARC code list for relators, sources, description conventions

Controlled vocabularies, thesauri and classification systems available in the WWW (Koch)

A-Z of Thesauri and Vocabulary Resources(HILT)

Traugott Koch(

Created: 2001-05-11
Last update: 2001-05-11