A COMPARISON OF 2 METHODS FOR INDEXING AND RETRIEVAL FROM A FULL-TEXTMEDICAL DATABASE

The objective of this study was to compare how well medical profession als are able to retrieve relevant literature references using two comp uterized literature searching systems that provide automated (non-huma n) indexing of content. The first program was SAPHIRE, which features concept-based indexing, free-text input of queries, and ranking of ret rieved references for relevance. The second program was SWORD, which p rovides single-word searching using Boolean operators (AND, OR). Sixte en fourth-year medical students participated in the study. The databas e for searching was six volumes from the 1989 Yearbook series. The que ries were ten questions generated on teaching rounds. All subjects sea rched half the queries with each program. After the searching, each su bject was given a questionnaire about prior experience and preferences about the two programs. Recall (proportion of relevant articles retri eved from the database) and precision (proportion of relevant articles in the retrieved set) were measured for each search done by each part icipant. Mean recall was 57.6% with SAPHIRE; it was 58.6% with SWORD. Precision was 48.1% with SAPHIRE VS 57.6% with SWORD. Each program was rated easier to use than the other by half of the searchers, and pref erences were associated with better searching performance for that pro gram. Both systems achieved recall and precision comparable to existin g systems and may represent effective alternatives to MEDLINE and othe r retrieval systems based on human indexing for searching medical lite rature.