Editorial
T
hree years ago I was able to report that
Design Studies had finally been included
into the Thomson/ISI citation index (in
the Science Citation Index Expanded). This is
the internationally leading citation index, which
allows comprehensive citation search access
through the Thomson/ISI Web of Knowledge. It
is also the most influential, in that it publishes
journal ‘impact factors’.
The ISI impact factor was originally developed in
the 1960s. Librarians and information scientists
had been evaluating journals for many years be-
fore then, but the ISI citation indexes and journal
citation reports (JCR) made it possible to compile
statistical reports on the output of journals and of
citation frequencies. As the Thomson organisa-
tion itself explains, ‘The JCR provides quantita-
tive tools for ranking, evaluating, categorizing,
and comparing journals. The impact factor is
one of these; it is a measure of the frequency
with which the ‘‘average article’’ in a journal has
been cited in a particular year or period. The an-
nual JCR impact factor is a ratio between citations
and recent citable items published. Thus, the im-
pact factor of a journal is calculated by dividing
the number of current year citations to the source
items published in that journal during the previous
two years.’ (http://scientific.thomson.com/free/
essays/journalcitationreports/impactfactor/)
Thus it takes three years of being included in the
citation index before an impact factor can be cal-
culated. Which means that the first impact factor
calculation for Design Studies was made last
year, for the year 2006. Why is the impact factor
important? Because it is supposed to embody
a measure of a journal’s quality or academic
‘prestige’ in its field. Roughly, the higher a jour-
nal’s impact factor, the higher is the frequency
that articles published in that journal get cited in
other journals. Thus a high impact factor indicates
that a journal carries articles that are regarded as
sufficiently useful, informative or important to
be cited by others. For some researchers, it is im-
portant to publish in journals with high impact
factors because their employer institutions or
funding bodies give more regard to such journals.
So how did we do? Not bad. The 2006 impact
factor for Design Studies came out at 0.807, which
is respectable. Some comparisons with a couple
of sister journals from Elsevier are Applied Ergo-
nomics with 0.757 and Computer-Aided Design
with 1.446. The truly stellar journals in terms of
impact factor are those such as Nature at 26.681
and Science at 30.028! Our own figure would
surely be higher if the Thomson/ISI citation index
(of over 6000 journals) actually included more
journals in our field, where our articles are cer-
tainly cited.
Of course, impact factors have to be interpreted
with some caution. Again, as the Thomson orga-
nisation itself explains, ‘The impact factor should
not be used without careful attention to the many
phenomena that influence citation rates, as for
example the average number of references cited
in the average article. The impact factor should
be used with informed peer review . Citation fre-
quencies for individual articles are quite varied.’
So a general impact factor for a journal does not
necessarily directly relate to each individual article
within it. However, it is usually the case that the
highest quality journals as judged by more
www.elsevier.com/locate/destud
0142-694X $ - see front matter Design Studies 29 (2008) 1e3
doi:10.1016/j.destud.2007.12.002
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