Morpheme-based, cross-lingual indexing for medical document retrieval

The increasing availability of machine-readable medical documents is not re ally matched with the sophistication of currently used retrieval facilities to deal with a variety of critical natural language phenomena. Still most popular are string-matching methods which encounter problems for the medica l sublanguage, in particular, concerning the wide-spread use of complex wor d forms such as noun compounds. We introduce a methodology for the segmenta tion of complex compounds into medically motivated morphemes. Given the sub language patterns in our data these morphemes derive from German, Greek and Latin roots. For indexing and retrieval purposes, such a morpheme dictiona ry may be further structured by defining the semantic relations among morph eme sets in order to build up a multilingual morpheme thesaurus. We present a tool for thesaurus compilation and management, and outline a methodology for the proper construction and maintenance of a multilingual morpheme the saurus. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.