Not all Journals are
Created Equal!
Using Impact Factors to Assess the Impact of a Journal
Objectives:
At the end of this talk, the participant will be able to:
1. Define Impact Factor (IF)
2. Explain how the impact factor relates to finding the
"best" journal in which to publish.
3. Find the impact factor of a journal using the LRC’s
Electronic Resources
The man who started it all!
Eugene Garfield
The article that got the ball rolling:
Why is this different?
 Based on law indexing (Shepard’s Citations) 1873
 Subject indexes to scientific literature were in existence
 Garfield suggests that each article is given a code and
all works that cited that article would be linked to the
original article.
First mention of Impact Factor
 Garfield recommends keeping track of who cited the
paper.
“In effect, the system would provide a complete listing, for
the publications covered, of all the original articles that
had referred to the article in question.” … Such an
“impact factor” may be much more indicative than an
absolute count of a scientist's publications.”
 Here impact factor refers to the impact of the article.
Impact Factors for Journals
 In the early 1960’s Irving H. Sher and Eugene Garfield
created the Journal Impact Factor to help select
journals for Science Citation Index (SCI).
 They knew that a core group of highly cited large
journals needed to be covered in SCI, but they also
wanted to include the small, but important review
journals which would not be included if they relied only
on publication or citation counts.
 Created the Journal Impact Factor
Journal Impact Factor
Formula
The number of times articles published in (2 years) were
cited by indexed journals
Total number of citable items (2 years)
In Simpler Terms
The impact factor is a measure
reflecting the average number of
citations to articles published in
science and social science
journals.
Other Methods
 Eigenfactor
 H Index (or H factor)
 Immediacy index
Eigenfactor
• Developed by Jevin West and Carl Bergstrom at the
University of Washington,
• Journals are rated according to the number of incoming
citations, with citations from highly-ranked journals
weighted to make a larger contribution to the Eigenfactor
than those from poorly-ranked journals.
• Eigenfactor score scales with the size of a journal.
• To allow per-article comparisons using the Eigenfactor
approach, the Article Influence score scales Eigenfactor
score by the number of articles published by the journal and
thus is directly comparable to impact factor.
Eigenfactor (cont)
 For more information, go to :
http://Eigenfactor.org
H Factor or H Index
Index that attempts to measure both the productivity and
impact of the published work of a scientist or scholar.
A scholar with an index of h has published h papers each
of which has been cited by others at least h times.
Serves as an alternative to more traditional journal impact
factor metrics in the evaluation of the impact of the
work of a particular researcher
Immediacy index
Measure of topicality and urgency of a scientific journal
Number of times articles published in year x were cited in
indexed journals during same year.
Number of articles, reviews, proceedings or notes
published in year x
What does it all mean?
How do Impact factors help
you find the best journal in
which to publish?
Limitations of the Impact Factor
 Self-citations
 Many times editors insist that authors cite works in that
journal
 Some disciplines tend to cite more than others
 Journals change their names thus affecting impact
factor for approximately two years
 Does not take into account negative citations
How do I find a journal impact
factor?
 Use the LRC’s Electronic Resources to go to Web of
Science
 Click on Additional Resources to find Journal Citation
Reports
Journal Citation Reports
JCR
 JCR distills citation trend data for 10,000+ journals from
more than 25 million cited references indexed by
Thomson Reuters every year
 Science Edition and Social Sciences Edition released
annually
 Science Edition covers 7,200+ journals in 171 subject
categories
 Social Sciences Edition covers 2,100+ journals in 55
subject categories
First log in to ER and find
Web of Science
Access JCR from the Web of
Knowledge
Scenario I
(We all have our dreams!)
 You have written an article and would like to have the
most visibility possible. You have a choice between
publishing in Science and Nature.
 Which should you choose, based on Impact Factor?
Search for individual journals
Subject Categories
View Journal data
Sort journals in the category
Full Record Page
Journal Rank in categories
Journal Rank in categories
Journal self citation
To provide one the ability to easily compare self-citation rates among journals
particularly as this influences Impact factor calculations.
Category Impact Data
Category Data – Median and Aggregate
Impact Factors
 The Median Impact Factor for the subject category of Pediatrics is 1.252
 The Aggregate Impact Factor for Pediatrics is 1.932
Access to JCR from the Web
of Science
Impact Factor Trend Graph
•Entry point into JCR from Web of Science
•Indicates the Journal’s Impact Factor over the latest five
years
Using JCR Wisely
You should not depend solely on citation data in your journal evaluations.
Citation data are not meant to replace informed peer review. Careful
attention should be paid to the many conditions that can influence
citation rates such as language, journal history and format, publication
schedule, and subject specialty.
The number of articles given for journals listed in JCR include primarily
original research and review articles. Editorials, letters, news items,
and meeting abstracts are usually not included in article counts
because they are not generally cited. Journals published in nonEnglish languages or using non-Roman alphabets may be less
accessible to researchers worldwide, which can influence their citation
patterns. This should be taken into account in any comparative journal
citation analysis.