AbstractOn‐line interactive literature searching systems have “come of age” and have revolutionized information retrieval techniques. They are now widely used for subject‐oriented searching. Much more than subject information is available in most of the data bases currently available, such as author names, corporate affiliations, journal titles, and CODEN. These are useful for bibliometric‐type studies, that is, quantitative analysis of the bibliographic features of a body of literature. Several examples are given, including journal comparison studies, corporate affiliation studies, and statistical studies.Inconsistencies and errors in data bases become important, and the searcher must be alert to their existence. Indexing policies of the different data bases must also be taken into cons