Key points are not available for this paper at this time.
Duplicate entries in Information Science Abstracts allowed for a study of the consistency of the indexing of this file. The results showed a bipolar distribution: indexing matched completely almost half of the time and did not match at all almost half of the time. The indexing policies of ISA require one mainheading and one or two subheadings per document. This restriction in the number of terms and the fact that ISA has a very small vocabulary from which to draw these terms may be the reason for this bipolar distribution. The indexing consistency was highest for the descriptors, drawn from a small controlled vocabulary, and lowest for identifiers, drawn from natural language or the controlled vocabulary. The data suggested that as the number of terms assigned per article increased indexing consistency decreased. © 1991 John Wiley & Sons, Inc.
Sievert et al. (1991) studied this question.