Zusammenfassung
The Medical Subject Headings (MeSH) thesaurus is a controlled vocabulary widely used in biomedical knowledge systems, particularly for semantic indexing of scientific literature. As the MeSH hierarchy
evolves through annual version updates, some new descriptors are introduced that were not previously available. This paper explores the conceptual provenance
of these new descriptors. In particular, we investigate
whether such new descriptors have been previously covered by older descriptors and what is their current relation to them. To this end, we propose a framework to
categorize new descriptors based on their current relation to older descriptors. Based on the proposed classification scheme, we quantify, analyse and present the
different types of new descriptors introduced in MeSH
during the last fifteen years. The results show that only
about 25% of new MeSH descriptors correspond to new
emerging concepts, whereas the rest were previously
covered by one or more existing descriptors, either implicitly or explicitly. Most of them were covered by a
single existing descriptor and they usually end up as
descendants of it in the current hierarchy, gradually
leading towards a more fine-grained MeSH vocabulary.
These insights about the dynamics of the thesaurus are
useful for the retrospective study of scientific articles
annotated with MeSH, but could also be used to inform
the policy of updating the thesaurus in the future.
Nutzer