VETERINARY SCIENCES: A BIBLIOMETRIC OVERVIEW Adam Finch Bibliometrics Analyst Wiley-Blackwell

- How Impact Factors are calculated and why they matter Veterinary Sciences: A Bibliometric Overview - The problems with Impact Factors - How to improve your Impact Factor - SCOPUS - Other metric and journal ranking systems - Author ranking systems

Impact Factor for JCR Year x = Citations in Year x to Papers from x-1 and x-2 Number of Articles & Reviews in x-1 and x-2 The Impact Factor Cites in 2007 to articles published in: 2006 =150 Number of articles published in: 2006 = = =56 Sum:462 Sum:112 Journal Impact Factor Calculation: Cites to recent articles 462 = Number of recent articles 112 For Example:

Subject Impact Factors & Other Metrics Journal Impact Factor - Immediacy Index Cites in Year X to source articles published in Year X - Cited Half Life The median age of the articles that were cited in Year X. Half of those articles that have been cited were published more recently than the cited half-life. - Median Impact Factor The median value of all individual journal Impact Factors in a given subject category. - Aggregate Impact Factor The number of citations from Year X to all articles in a given subject category published in Years X-1 and X-2, divided by the number of articles from all journals in the category published in Years X-1 and X-2.

Veterinary Sciences – Subject Impact Factors

 Informing editorial decisions  Attracting the best authors  Encouraging librarians to subscribe - Identifying the most frequently cited authors - Identifying the hot topics - Identifying the less frequently cited papers - Increasing the Impact Factor increases readership and extends journal reach - Publication in high-impact journals lends authority to articles - The next Research Assessment Exercise will include a bibliometric criterion - Identifying high-impact journals for subscription - Prioritising library provision of access to subscribed content - Bibliometrics have been an established tool since the 1970’s The Uses of Impact Factors and the Web of Science

Impact Factors are therefore crucially important… …but far from infallible…

 Requirements for inclusion  Indexing for the Impact Factor - Limiting inclusion is important to maintain the value of a cite. - Tests for inclusion do not account, for example, for a journal with minimal niche appeal but massive citation activity. - Standards applied today are not the same as the standards applied originally. - Wide variation in subject coverage – eg, Arts & Humanities 50% of all journals indexed, Chemistry 93% indexed. Veterinary Sciences have 80% coverage. (Moed, H.F. (2005) Citation Analysis in Research Evaluation,(Dordrecht: Springer). Page 126, Table 7.3). - Issues indexed at the end of a calendar year have less time to accrue citations within the Impact Factor window. The Problems with Impact Factors and the Web of Science

 Error correction  Impact Factor inflation - Because Impact Factors are released once per year rather than as a rolling service, there is a limited facility to report errors in calculation or listing of source items. - If source items or citations have not been counted correctly historically, there is no way to correct for the inaccuracy. - Journal Impact Factors are seeing inflation of approximately 2.6% per annum Benjamin M. Althouse, Jevin D. West, Ted C. Bergstrom, and Carl T. Bergstrom, "Differences in Impact Factor Across Fields and Over Time" (April 23, 2008). Department of Economics, UCSB. Departmental Working Papers. Paper ) - Variation in the inflation across subject areas is making worse an already difficult variation between ISI categories. The Problems with Impact Factors and the Web of Science

 Subject area dependency  Self citation - Wide variations in subject areas – eg, 2007 Aggregate Impact Factor for Oncology was 4.551; for Vet Sciences, 1.124; for Area Studies, There are variations even within similar spheres – eg, 2007 Aggregate Impact Factor for Psychology, Developmental was 2.112; for Psychology, Psychoanalysis, If an area is not currently well-indexed (eg, Philosophy of Education) this is an entry barrier to all journals in that subject as cross-citation is not counted. - Criteria for inclusion in a subject area not clear or easily appealed. - Journals have widely varying levels of self-citation; anywhere from a twenthieth to a third of all citations can be self-cites. - There is anecdotal evidence from some subject areas of Editors insisting on authors inserting into their articles unnecessary citations to their journal – a practice no publisher should support. - ISI does suspend journals from the JCR if they have evidence of systematic abuse. The Problems with Impact Factors and the Web of Science

 Case studies  Niche areas - Case studies are included in the denominator of the Impact Factor but are themselves cited less frequently than articles; this significantly dilutes Impact Factors in the subject area. - Case reports are sometimes included in the denominators of other subjects’ Impact Factors but sometimes they are not. This inconsistency is particularly problematic for journals that span several subject areas. - Journals in Veterinary Sciences often address niche topics. - Citation levels between these niche areas vary significantly. - This makes it difficult to compare Veterinary Sciences journals even within the subject category. The Problems with Veterinary Sciences

 Have a basic level of citation activity  Address a niche area with the journal How to Get an Impact Factor  Be ‘international’  Conform to journal publishing norms - Regular publication - Peer reviewed...or VERY regional...

 Balancing the Impact Factor denominator  Don’t ask authors to increase journal self- citation Improving Impact – Basic Tips  Maximising readership of best papers  Publishing themed collections  Publishing Reviews  Publishing materials at the start of the calendar year  Minimising publication times  Identifying and focusing on the hot topics

Talk to your publisher about what they can do… Improving Impact – Using Analyses

Improving Impact – Wiley-Blackwell Analyses  Country  Institution  World Region  Keywords  Most/Least Cited Articles  Impact Factor Deconstruction & Prediction  Look at article contribution to Impact Factor

SCOPUS >3,400 Life Sciences Journals >5,500 Physical Sciences Journals >2,800 Social Sciences Journals >5,300 Health Sciences Journals Only goes back to 1996 (Web of Science goes back to 1950’s) SCImago calculates ‘unofficial’ Impact Factor for SCOPUS data Variety of online analysis tools (most Web of Science analysis is offline)

Other Ranking Systems – SJR (SCIMago Journal Rank) Like the Impact Factor, the denominator is the number of source documents published by the journal. Weights citations so that a citation from a ‘good’ journal is worth more, like Google’s PageRank. Uses a three year citation window. Based on data from Scopus for 1996 onwards rather than the Web of Science. Designed by SCIMago, a team involved in Scopus’ creation. Journal, country and subject ratings are produced. Currently free and searchable. Iterative process, therefore more difficult to predict or deconstruct.

Other Ranking Systems - Eigenfactor The EigenFactor is the percentage of citations that a journal receives from the ~8,000 publications. Like the SJR, weights citations using PageRank. Compensates for varying levels of citation activity across different subject areas. The citation window is 5 years instead of 2. All self-citations are omitted. Currently free and searchable. Calculation is based on algorithms and matrixes, making it more difficult to analyse or predict. Based on ISI’s Web of Science data.

Other Ranking Systems – Transparency versus Accuracy IF Year x = Year x Cites to Papers from x-1 and x-2 Source items x-1 and x-2

Author Ranking Systems H-Index Proposed by Jorge Hirsch in An individual has a index of h, when they have published at least h papers, each of which has been cited at least h times So, an h-index of 10 means that the author has published 10 papers cited at least 10 times each. Numerous criticisms have been levelled at the metric, but it is still very widely used.

Author Ranking Systems G-Index Proposed by Leo Egghe in An individual has a g-index of g when they have published at least g papers which have in total been cited more than g 2 times. So, a g-index of 10 means that an author has produced 10 publications, which have in total accrued at least 100 citations amongst them.

Author Ranking Systems H(2)-Index Proposed by Marek Kosmulksi in An individual has an index of k when each publication in a ranked list has been cited at least k 2 times. So, an H(2) of 10 means that the 10 th most cited article has been cited at least 100 times.

Author Ranking Systems a index m quotient m index r index ar index h w index ?

The Road Ahead At the moment, it’s the Wild West – the uncivilised frontier being tapped for gold… ISI will face the new competition from SCOPUS, hopefully initiating a service/facility ‘arms race’… Development of yet more new methodologies – eg, Google Scholar and INK for indexing, more author indexes, more ranking systems… Over time, the merits of some systems will win out and consensus will emerge… So should Editors focus on metrics or serving the community? To hedge your bets, go for the latter…

Thank You Adam Finch Wiley-Blackwell, Oxford, UK