Optimal document-indexing vocabulary for MEDLINE

Abstract

The indexing vocabulary is an important determinant of success in text retrieval. Researchers have compared the effectiveness of indexing using free-text and controlled vocabularies in a variety of text contexts. A number of studies have investigated the relative merits of free-text, MeSH and UMLS Metathesaurus indexing vocabularies for MEDLINE document indexing. Most of these studies conclude that controlled vocabularies offer no advantages in retrieval performance over free-text. This paper offers a detailed analysis of prior results and their underlying experimental designs. The analysis indicates that there are a number of open questions relevant to the overall debate on indexing vocabularies for MEDLINE. This paper also offers results from a new experiment assessing eight different retrieval strategies. These strategies involve document indexing via free-text, MeSH and several alternative combinations of the two vocabularies. The results indicate that MeSH does have an important role in text retrieval. Copyright © 1996 Elsevier Science Ltd.