This study investigated the in-house use half-life of journals in the Library of Veterans General Hospital, Taipei, and their citation half-life, and the difference between them. The use study employed the sweep method and the study period lasted for 6 months. The citation half-life of each journal of this study was based on the data listed in the Science Citation Index, Journal Citation Reports, 1993. The results of this study illustrate that publication frequency, journal age, language, and country of publication, and subject category all are related to both use and citation half-lives. In addition, the use half-life also reflects the extent of holdings of particular titles in the local library. The mean use half-life of the total 835 journals is 3.43 years, which is significantly shorter than the mean citation half-life, 6.28 years. The difference between mean use half-life and mean citation half-life is 2.85 years, and is statistically significant as revealed by the t test.
Journal of the American Society for Information Science 49(14), pp.1283-1292