Reedijk, J (Reedijk, Jan); Moed, HF (Moed, Henk F.) Is the impact of journal impact factors decreasing?

[Eugene Garfield]

E-mail Address: moed at cwts.leidenuniv.nl

Author(s): Reedijk, J (Reedijk, Jan); Moed, HF (Moed, Henk F.) 

Title: Is the impact of journal impact factors decreasing? 

Source: JOURNAL OF DOCUMENTATION, 64 (2): 183-192 2008 

Language: English 

Document Type: Article 

Author Keywords: information retrieval; electronic journals; user studies 

Keywords Plus: BIOMOLECULAR CHEMISTRY; CITATIONS; SCIENCE; INACCURACIES; 
INDICATORS 
Abstract: Purpose - The purpose of this paper is to examine the effects of 
the use of the citation-based journal impact factor for evaluative 
purposes upon the behaviour of authors and editors. It seeks to give a 
critical examination of a number of claims as regards the manipulability 
of this indicator on the basis of all empirical analysis of publication 
and referencing practices of authors and journal editors.

Design/methodology/approach - The paper describes mechanisms that may 
affect the numerical values of journal impact factors. It also analyses 
general, "macro" patterns in large samples of journals in order to obtain 
indications of the extent to which such mechanisms are actually applied 
oil a large scale. Finally it presents case studies of particular science 
journals ill order to illustrate what their effects may be ill individual 
cases.
Findings - The paper shows that the commonly used journal impact factor 
can to some extent be relatively easily manipulated. It discusses several 
types of strategic editorial behaviour, and presents Cases in which 
journal impact factors were - intentionally or otherwise - affected by 
particular editorial strategies. These findings lead to the conclusion 
that one must be most careful in interpreting and using journal impact 
factors, and that authors, editors mid policy makers must be aware of 
their potential manipulability. They also show that some mechanisms occur 
as of yet rather infrequently while for others it is most difficult if not 
impossible to assess empirically how often they are actually applied. If 
their frequency of occurrence increases, one should come to the conclusion 
that the impact of impact factors is decreasing.

Originality/value - The paper systematically describes a number of claims 
about the manipulability of journal impact factors that are often based 
on "informal" or even anecdotal evidences and illustrates how these claims 
can be further examined in thorough empirical research of large data 
samples. 

Addresses: [Moed, Henk F.] Leiden Univ, Ctr Sci & Technol Studies CWTS, 
Leiden, Netherlands; [Reedijk, Jan] Leiden Univ, Leiden Inst Chem, NL-2300 
RA Leiden, Netherlands 

Reprint Address: Moed, HF, Leiden Univ, Ctr Sci & Technol Studies CWTS, 
Leiden, Netherlands. 

E-mail Address: moed at cwts.leidenuniv.nl 

Cited Reference Count: 25 

Times Cited: 0 

Publisher: EMERALD GROUP PUBLISHING LIMITED 

Publisher Address: HOWARD HOUSE, WAGON LANE, BINGLEY BD16 1WA, W 
YORKSHIRE, ENGLAND 

ISSN: 0022-0418 

DOI: 10.1108/00220110810858001 

29-char Source Abbrev.: J DOC 

ISO Source Abbrev.: J. Doc. 

Source Item Page Count: 10 

Subject Category: Computer Science, Information Systems; Information 
Science & Library Science 

ISI Document Delivery No.: 341RY 

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