QUANTITATIVE COMPARISON OF PRE-EXPLOSIONS AND SUBHEADINGS WITH METHODOLOGIC SEARCH TERMS IN MEDLINE

Objective: To compare the retrieval characteristics of subheadings wit h methodologic textwords and MeSH terms in MEDLINE for identifying sou nd clinical studies on the etiology, prognosis, diagnosis, prevention and treatment of disorders in general adult medicine. Design: Analytic survey of the information retrieval properties of methodologic textwo rds, single methodologic MeSH terms, pre-explosions and subheadings se lected to detect studies meeting basic methodologic criteria for direc t clinical use in general adult medicine. Measures: The sensitivity, s pecificity, and precision of search terms were determined by comparing the citations retrieved by the search strategies in MEDLINE with that of a manual review (the gold standard) of all articles in 10 internal and general medicine journals for 1986 and 1991. Results: For treatme nt and diagnosis in 1991, and treatment, diagnosis, and etiology in 19 86, pre-explosions yielded the highest sensitivity, with typical absol ute increases exceeding 15%. For etiology and prognosis in 1991, and p rognosis in 1986, textwords or MeSH terms yielded the highest sensitiv ity. In all cases the increase in sensitivity was coupled with a loss in specificity and precision. Conclusions: Compared with searching wit h single methodologic textwords and subject headings, the detection of sound clinical studies on the diagnosis and treatment of disorders in general adult medicine was consistently enhanced by searching with pr e-explosions, but at a price of decreased specificity and precision.