Using unbound subheadings to increase recall in MEDLINE.
Indexers use subheadings more often than their equivalent main headings. Of a selected group of subheadings, one third had twice as many postings as the equivalent exploded main heading. Searching the subheading as an unbound heading, detached from any main heading descriptors, can be an efficient way of increasing search retrieval.
D000043:Abstracting and Indexing; D008523:MEDLARS; D014481:United States