Scatter and obsolescence of journals cited in theses and dissertations of librarianship

Abstract

This article analyzes the bibliometric features (the number of pages, completion years, the fields of subject, the number of citations, and their distribution by types of sources and years) of 100 theses and dissertations completed at the Department of Librarianship of Hacettepe University between 1974 and 2002. Almost a quarter (24%) of all dissertations were on university libraries, followed by public libraries (9%). Doctoral dissertations were, on average, twice as long as master's theses and contained 2.5 times more citations. Monographs received more citations (50%) than journal articles did (42%). Recently completed theses and dissertations contained more citations to electronic publications. Fourteen (or 3.2% of all) journal titles (including Türk Kütüphaneciliği, College & Research Libraries, and Journal of the American Society for Information Science) received almost half (48.9%) of all citations. Eighty percent of journal titles were cited infrequently. No correlation was found between the frequency of citations of the most frequently cited journals and their impact factors. Cited journal titles in master's and doctoral theses and dissertations overlapped significantly. Similarly, journal titles cited in dissertations also overlapped significantly with those that were cited in the journal articles published in the professional literature. The distribution of citations to foreign journal titles fit Bradford's Law of Scattering. The mean half-life of all cited sources was 9 years. Sources cited in master's dissertations were relatively more current. Single authorship was the norm in cited resources. Coupled with in-library use data, findings of the present study can be used to identify the core journal titles in librarianship as well as to evaluate the existing library collections to decide which journal titles to keep, discard, or relegate to off-site storage areas.