elsevier - medicres world congress 2011
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Measuring Journal PrestigeTRANSCRIPT
Measuring Journal and Research Prestige
Stephen Troth26th March 2011
[email protected] International Conference on
Good Medical Research
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Opening Questions What is the best scientific journal that you know of?
Why is that one the best?
Why can’t another journal be just as good as that one?
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Objectives Why is there a need to discern quality among different
journals? What metrics are used to compare journals? Which journal is appropriate for me to submit my
research to?
Why is there a need to discern quality among different journals?
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Growth of peer-reviewed journals
“This is truly the decade of the journal and one should seek to limit their number rather than
to increase them, since there can be too many periodicals.”
(1789)
Neues medicinisches Wochenblatt fur Aerzte
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Growth of scholarly journals
0
5000
10000
15000
20000
25000
<1900 1900s 1910s 1920s 1930s 1940s 1950s 1960s 1970s 1980s 1990s >2000Decade
Nu
mb
er
of
Ac
tiv
e,
Pe
er-
Re
vie
we
d J
ou
rna
ls
Source:
~3% per annum• Number of journals and disciplines is increasing
• The need to discern journal quality becomes that much more important
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Journal Competition
• Journals must vigorously compete with each other for the best papers and the best authors
• The concept of journal prestige originates from this competition
For example: In the category of “Analytical Chemistry”
Analytical Chemistry
Analytica Chimica Acta
Analytical Biochemistry
Analytical and Bioanalytical Chemistry
Journal of Electroanalytical Chemistry
Analyst
Electroanalysis
Analytical Sciences
Journal of Analytical Chemistry
Current Analytical Chemistry
Reviews in Analytical Chemistry
And >50 others!
How can you tell which of these are high quality journals?
What metrics are used to compare journals?
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Overview of Journal Metrics
Impact Factor H-index SCImago Journal Rank Usage Others
• Journal citation data and bibliometrics can be used to measure the impact or influence of articles, authors, and journals
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Impact Factor
• Citation index of Science, Social Science, Arts & Humanities journals
• Impact Factors of Science and Social Science journals
Impact Factor is the most well-known citation metric
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Impact Factor Definition & Calculation
IF is published 6 months after the end of the year it relates to (i.e. 2006 data published in mid-2007)
Definition: A ratio between citations and recent citable items published in a journal
(i.e. the average number of citations received per published article)
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The Impact Factor
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Citations to non-source items (editorials, letters, newsitems, book reviews, abstracts, etc) may inflate the IF
The Impact Factor anomaly
To all items (regardless of type)
Of source items (“articles” and “reviews”)
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Influences on the IF: Article TypeC
itatio
ns
Articles
Reviews
Years after publication
Notes
4 8 12 160 2 6 10 14 18 20
Impact Factor
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0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5
Mathematics & Computer Sciences
Social Sciences
Materials Science & Engineering
Biological Sciences
Environmental Sciences
Earth Sciences
Chemistry & Chemical Engineering
Physics
Pharmacology & Toxicology
Clinical Medicine
Neuroscience
Fundamental Life Sciences
Mean Impact Factor (1998)
Influences on the IF: Subject Area
CHARACTERIZATION & TESTING
0.000 0.500 1.000 1.500 2.000 2.500 3.000
PAPER & WOOD
TEXTILES
CERAMICS
COMPOSITES
COATINGS & FILMS
MULTIDISCIPLINARY
POLYMER SCIENCE
NANOSCI & NANOTECH
BIOMATERIALS
Aggregate 2006 IF
Materials Science disciplines
Impact Factors carry little meaning unless they are compared
within the same subject area and
discipline
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Influences on the IF: Subject Area
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2008 IF
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Impact Factor Use and Abuse
• Used for library collection development
• Open to manipulation by authors, reviewers,editors and publishers
• Used to compare journals of different types • Used to compare journals in different fields • Used to derive a ‘personal IF’
• Used as a lone proxy for journal ‘quality’
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Impact Factor doubts
June 5, 2006
October 14, 2005
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Elsevier’s philosophy on the IF
“Elsevier uses the Impact Factor as one of a number of performance indicators for journals. It acknowledges the many caveats associated with its use and strives to share best practice with its authors, editors, readers and other stakeholders in scholarly communication. Elsevier seeks clarity and openness in all communications relating to the IF and does not condone the practice of manipulation of the IF for its own sake.”
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Other IF-related metrics Cited Half-life
The cited half-life for the journal is the median age of its articles cited in the current JCR year
Immediacy Index The immediacy index is the average number of times an
article is cited in the year that it is published Influence
The influence indicates the share of citations that an individual title or publisher has within a given subject category or subject group
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h-index
• Proposed by physicist Jorge Hirsch in 2005
• Rates individuals or journals based on career publications
• Incorporates both quantity (no. of publications) and quality (no. of citations)
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Calculating the h-index
If you list a scientist’s papers in descending order of the number of citations received to date, his/ her h-index is 8 if 8 papers have each received 8 or more citations
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h-index
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h-index for journals
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SCImago Journal Rank
Produced by experts in Spain Data sourced from Scopus and incorporated in it A ratio of citations in current year to articles published in the
previous 3 years Citations are weighted by the SJR of the
citing journal (like Google weights links to webpages)
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SCImago Journal Rank
Note European decimal notation!
New metrics : Popularity
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Free (eigenfactor.org); also now part of the JCRSimilar to Impact Factor, but considers 5 yearsSelf-citations excludedCitations weighted by EF of the citing journal
Eigenfactor Article Influence
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Usage Usage is a new concept for measuring journal value and
impact Typically defined as when a full-text article is
downloaded or viewed COUNTER is attempting to standardize usage reporting
and develop a “Usage Factor” metric Libraries already use usage statistics heavily to evaluate
their collections and spending Authors also interested to see how much their works are
used
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Summary of Different Metrics H-index, SJR, and usage are gaining weight as more
users include them as evaluative tools
Other metrics are also being studied and developed not mentioned here: Eigenfactor
But IF is still the industry-standard and first metric that is used to assess journal importance
Which journal is appropriate for me to submit my research to?
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Journal Selection
How would you select among the journals of “Analytical Chemistry”?
Analytical Chemistry
Analytica Chimica Acta
Analytical Biochemistry
Analytical and Bioanalytical Chemistry
Journal of Electroanalytical Chemistry
Analyst
Electroanalysis
Analytical Sciences
Journal of Analytical Chemistry
Current Analytical Chemistry
Reviews in Analytical Chemistry
And >50 others!
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Journal Selection
Selection of a journal will depend on many factors in addition to journal metrics
The aims and scope of the journal The type of manuscript you have written (review, letter, articles) The specific subject area The significance of your work The prestige/quality of the journal The respect of the editors in the field The editorial and production speed of the journal The community and audience associated with the journal The coverage and distribution (regional, international)
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Summary
Why is there a need to discern quality among different journals? Increasing number of journals and disciplines
What metrics are used compare journals? Impact Factor H-index SCImago Journal Rank SNIP/Eigenfactor Usage
Which journal is appropriate for me to submit my research to? Consider the significance and scope of your work. Ask professors in your field
what journal would be appropriate for the area and level of research you have conducted
Consider the aims, scope, subject area, prestige, editors, editorial and production speed, community/audience, and coverage of a journal