INDEXING BIOMEDICAL DOCUMENTS - FROM THESAURAL TO KNOWLEDGE-BASED RETRIEVAL-SYSTEMS

This position paper advocates interactive knowledge-based indexing of the National Library of Medicine's (NLM's) MEDLINE database. Initially, it establishes that in the current setting concept indexing is needed and cannot be fully automated. Compatibility between conventional and knowledge-based indexing is then highlighted, followed by discussion of indexing as a cognitive process. The section on knowledge-based indexing systems describes how NLM's MedIndEx prototype addresses problems in conventional indexing, and includes the contention that constructing a knowledge base adapted from a conventional classified thesaurus and indexing scheme is not as daunting as it may seem. Extension of the indexing prototype to an intelligent search assistant illustrates use of the same knowledge base to integrate indexing and retrieval applications. The paper concludes with selections from the Milstead report on the state of the art of subject analysis for large multidisciplinary bibliographic databases, followed by suggested future directions for knowledge-based indexing.