Structural measures to track the evolution of SNOMED CT hierarchies

Tracking the Remodeling of SNOMED CT's Bacterial Infectious Diseases

SNOMED CT's content undergoes many changes from one release to the next. Over the last year SNOMED CT's Bacterial infectious disease subhierarchy has undergone significant editing to bring consistent modeling to its concepts. In this paper we analyze the stated and inferred structural modifications that affected the Bacterial infectious disease subhierarchy between the Jan 2015 and Jan 2016 SNOMED CT releases using a two-phased approach. First, we introduce a methodology for creating a human readable list of changes. Next, we utilize partial-area taxonomies, which are compact summaries of SNOMED CT's content and structure, to identify the "big picture" changes that occurred in the subhierarchy. We illustrate how partial-area taxonomies can be used to help identify groups of concepts that were affected by these editing operations and the nature of these changes. Modeling issues identified using our two-phase methodology are discussed.

A unified software framework for deriving, visualizing, and exploring abstraction networks for ontologies

Software tools play a critical role in the development and maintenance of biomedical ontologies. One important task that is difficult without software tools is ontology quality assurance. In previous work, we have introduced different kinds of abstraction networks to provide a theoretical foundation for ontology quality assurance tools. Abstraction networks summarize the structure and content of ontologies. One kind of abstraction network that we have used repeatedly to support ontology quality assurance is the partial-area taxonomy. It summarizes structurally and semantically similar concepts within an ontology. However, the use of partial-area taxonomies was ad hoc and not generalizable. In this paper, we describe the Ontology Abstraction Framework (OAF), a unified framework and software system for deriving, visualizing, and exploring partial-area taxonomy abstraction networks. The OAF includes support for various ontology representations (e.g., OWL and SNOMED CT's relational format). A Protégé plugin for deriving "live partial-area taxonomies" is demonstrated.