The MCDU Project focused on analyzing cataloger’s use of MARC fields, subfields, and other content designation structures (CDS). The first phase of that analysis examined the use of MARC CDS based on format of material and source of cataloging. We know, however, that over time the CDS available to catalogers changed as MARC evolved. New CDS were added, some were deleted, and format integration brought together similar CDS from various formats.
The MCDU Project Team carried out a second phase of analysis that attempted to take into account the dynamic and evolving nature of MARC and the CDS available to catalogers over time. A document listed below describes the methodology for this analysis. In addition, the frequency counts and tabulation upon which this summary is based are available in a set of data reports listed below.
Before this analysis could be carried out, it was first necessary to document when new fields, subfields, and other CDS were added, deleted, and/or changed. No existing database or resource existed that documented the evolution of MARC CDS. The MCDU Project created HistoriMARC, a database that stores in structured form all available information about MARC bibliographic CDS from 1972 through 2004. HistoriMARC was the enabling tool for carrying out the analysis of MARC use over time since it allowed us to manipulate and reuse data about CDS additions, deletions, and other changes in our analysis. A summary of the results and findings is provided in the document, Catalogers’ Use of MARC Content Designation over Time: An Analysis of MARC Records from 1972 to 2004.