Information retrieval in medicine: state of the art.

Conventional information retrieval systems usually involve searching by terms from controlled vocabularies or by individual words in the text. These systems have been commercially successful but are limited by several problems, including cumbersome interfaces and inconsistency with human indexing. Research on methods that automate indexing and retrieval has been performed to address these problems. The three major types of automated systems are vector-based, probabilistic, and linguistic. This article describes these systems and provides an overview of the field of information retrieval in medicine.