Thesaurus-enhanced search interfaces

User interfaces to information retrieval systems play a major role in assisting users to search, browse and retrieve information relevant to their needs. This paper provides a review of a category of information retrieval interfaces that are enhanced by incorporating standard thesauri as part of their searching and browsing facilities. A brief account of the rationale behind the integration of thesauri as search aids in such interfaces is provided, based on research literature related to information searching behaviour, information retrieval interface evaluation, search term selection and query expansion. Two categories of search interfaces enhanced with thesauri are examined: those associated with research-based programmes and commercial web-based interfaces to bibliographic databases. Six commercial web-based databases are compared in terms of their thesaurus interface features. It is concluded that, although the number of thesaurus-enhanced interfaces is growing, few studies have focused on user interaction with these interfaces or fully explored the ways in which they can assist users in the search process.