Reading factor: a new bibliometric criterion for managing digital libraries.

Although various methods are used to evaluate biomedical journals, there is no standard reference for fully assessing the impact of a journal in clinical medicine [1]. The utility or influence of a given paper on diagnosis or therapeutics has not been clearly defined. This study presents a novel mode of evaluation. In the research literature, an acknowledged criterion of value is the degree of influence on secondary papers. A citation by other articles is accepted as a fair estimate of the value or importance of a publication [2]. The impact factor (IF), published in the Science Citation Index (SCI) Journal Citation Reports (JCR), is based on a bibliometric analysis of science journals in the ISI database [3]. Although it has been criticized [4–8], IF is the most common bibliometric criterion for ranking and evaluating biomedical journals [9]. As IF represents, by its nature, an indirect criterion, a direct measure of journal use should be considered. The number of times a publication is consulted is an objective criterion of use. The recent availability of digital versions of major biomedical journals presents an opportunity to directly measure their electronic consultation rates. This paper describes a way to measure the electronic consultation rate that the authors have termed the reading factor (RF), in direct correlation to the impact factor. RF measures the interest in a journal within the limit of a given readership. It is a direct measurement of journal use that is related to both clinical medicine and library or information science. Results of the observed distribution of RF for the year 1998 and IF for 1997 are shown in Table 1. The Rouen University Hospital (RUH) medical digital library was created in 1997. This library allows all 304 RUH senior physicians to access MEDLINE, forty-six electronic full-text journals, and some selected electronic books from their offices at no charge [10].