Glossary
Glossary
Bias: statistic-epidemiological skewing
Difference test for two shared values resulting
from two very large independent samples: These statistics hold
for the predictions of language distributions that, on the one hand,
the tested medical databases may be viewed as random samples from
the (same) universe of international medical articles, that secondly,
subjects areas are comparable, and that no disparate qualitative standards
between these systems occur.
EMBASE: Excerpta Medica Database/ Elsevier
Science B.V. Amsterdam
ISI: Institute for Scientific Information - Thomson
Scientific, Philadelphia/ USA
JCR: annual Journal Citation Reports,
by ISI; there are ‘Science Editions’ (Medicine,
Natural and Applied Sciences) as well as ‘Social Science
Editions’
MEDLINE: Index Medicus On-Line/ National
Library of Medicine, created in the USA (NLM)
SCI: Science Citation Index (also: ”Current
Contents”)/ ISI
SCISEARCH: Database version of SCI
at hosts DIMDI, STN Karlsruhe, DIALOG
SCI Medicine segment: a constructed
part of SCI, comprising the referral documents relating to medicine
and related areas (constructed in this work on the basis of the
pertinent 65 journal classification codes in SCI)
IF: Journal Impact Factor (11). The
formula for the year 2000 is presented in Fig. [1]:
Fig. 1 Journal Impact Factor (11):
formula for the year 2000.
*) as documented in
the bibliographic databases of ISI
So, an Impact Factor (IF) in the annual Journal
Citation Reports (JCR) greater than, or equal to, unity is
reported for a journal which published in 1998 - 1999,
for example, 100 citable articles according to the Science Citation
Index - SCI (original articles, short communications, reports,
reviews - so-called meaty articles) and whose articles
are cited at least 100 times in the subsequent year (2000) in the
literature databases produced by the Institute for Scientific Information - Thomson
Scientific (ISI).
However, the entirety of cited document types enters the numerator
of the IF formula ([11]), i. e., cited editorials, letters
and conference reports are added to the meaty articles’ citations.
Background and objective
Background and objective
Critical analyses [(13], [14], [18], [20]) of the annual Journal Citation Reports speak of a language bias, i. e., a skewing
of results in the calculation of the JCR impact factors. This is
reportedly due to the preferential selection of English-language
sources relative to those in other languages. The IF is supposed
to be a measure of the citation rates of scientific journals ([11])
and is internationally applied for academic evaluations ([5], [12]).
Repercussions of the JCR on German medical publishing have been
extensively discussed ([3], [4], [6], [8], [19]); the Zurich gynecologist
Haller ([15]) even raised the question, ”Is the IF killing
the German language?”
The JCR are based on evaluations of cited references in publication
records stored in ISI databases. E. Garfield, founder of ISI, designated
the JCR as a by-product of the Science
Citation Index and the Social Science Citation Index ([10]). So the
annual JCR Science Editions (medicine, natural and applied sciences)
are derived from SCI data. In the literature there is a lack of
concrete numbers on the distribution of publication languages in
the JCR as well as in the underlying SCI database. Hence, the following questions
have been raised:
-
What is the representation of
publication countries and languages for journals in the JCR Science
Editions in their entirety and in the area of medicine?
-
Is the distribution of publication languages in the
SCI similar to that in other pertinent medical literature databases?
Methodology
Methodology
JCR
Data on publication countries and languages were researched and
evaluated for the JCR 1997 and 1998 Science Editions (CD ROMs, November
1998 and 1999). Country data in the JCR were derived from publisher
addresses. Data on publication languages referred to the entire
volume of a journal. Only the designations English (E)
and Multi-Language (ML) were used.
ML periodicals, however, often contained articles predominantly
in English. SERLINE/NLM and MEDIZET/Deutsche Zentralbibliothek
der Medizin (ZBMED) are journal cataloguing databases using
mostly different classifications in these cases. For example, we
found:
-
Tropical
Medicine & International Health (JCR: ML; SERLINE/MEDIZET
classification: English; 1990 - 2001
proportion of English-language articles in the SCI: 98.1 %)
-
Experimental Brain Research (JCR:
ML; SERLINE/MEDIZET: English; SCI: 100 % English
articles)
-
Ultrasound in Medicine and Biology (JCR:
ML; SERLINE/MEDIZET: English; SCI: 100 % English
articles)
Conversely, a majority of the papers in English-designated
JCR journals could also be written in one other language. Four relevant
examples were compared with data reported in both SERLINE and MEDIZET.
The English-language share of individual publications reported for
the 1990 - 2001 SCI is given in parentheses:
-
Annales
d’Urologie: Language French in SERLINE and MEDIZET
(SCI: 7.3 % articles in English)
-
Deutsche Medizinische Wochenschrift: German;
English editions 1956 - 1970; 1971 - 1973
(SCI: 0.1 % in English)
-
Semaines des Hopitaux: French
(SCI: 0.2 % in English)
-
Zeitschrift fuer Kardiologie: German
(SCI: 9.1 % in English)
Therefore, statistical findings based on language classifications in
JCR should be interpreted with caution.
In order to demonstrate a possible connection between IF magnitude
and English-language share, the percentages classified in the JCR
1997 and 1998 as English or ML periodicals were analyzed as a function
of IF. Therefore, IF intervals of width 0.5 were formed: 0.000 - 0.500,
0.501 - 1.000,..., 5.501 - 6.000,
6.000+.
Using the JCR 1998 journal subject classifications (analogous
codes also exist in the SCI) a journal group M (Medicine and Related
Fields) was selected from all JCR periodicals. This JCR segment
should correspond somewhat to the coverage of the MEDLINE/EMBASE
databases. So language shares specifically
in medicine as a function of IF magnitudes could also be considered. Group
M journals were listed among journals
with 65 classification codes (list available upon request) from
medicine and related fields. In the case of multiple categories
in the JCR 1998, the first code took precedence.
Literature Databases
In bibliographic databases, language designations always refer to
individual documents; however, in the JCR, they refer to entire
volumes. Each database record refers to one publication and contains
bibliographic data, key words and often abstracts. In addition,
cited references are stored in the Science Citation Index.
The SCI (database version SCISEARCH) covers the fields of medicine
and the natural and applied sciences. Comparable in size and specializing
in medicine and related fields, MEDLINE and EMBASE cover, respectively,
45 % and 44 % of the scope of
the SCI. With respect to its source material, MEDLINE is generally oriented
to the United States. EMBASE focuses on European and on pharmacological
literature and significantly complements MEDLINE search results
([1], [17], [22], [23], [24]).
The three databases mentioned were searched at DIMDI (German
Institute for Medical Documentation and Information) (7) using grips commands. Determined was the number
of records for the data field Language (LA),
which specifies the language of the original text. The publication
years 1995 - 2000 were chosen. This time
span covers the evaluation period 1997 and 1998 for the IF calculation
along with 1995 - 1997 (Fig. [1]) and includes the three following
years to provide a sense of the possible trends of language distribution
in the database.
To provide thematic comparisons, the database category ’’medicine
and related areas’’ was formed using the 65 SCI
classification codes. This category provides content similar to
that of MEDLINE and EMBASE. In the area of medicine, the two SCI
subfiles SCI-CLIN and SCI-BIOM were defined by the publisher up
to and including the year 2000.
The SCI medicine section covered twice as many documents as SCI-CLIN
(47.77 million versus 23.71 million) for the period 1990-XII.3.2001.
However, SCI-CLIN was hardly a proper subset of the SCI medicine
section, but covered 1,6 % other documents for
the same period.
The scope and the scientific relevance of the constructed SCI medicine
section were examined using test searches whose results were compared
with those from SCI-CLIN, SCI-BIOM and SCI-CLIN+SCI-BIOM.
Using medical terms, for example, such as myocardial
infarct, blood pressure, gene therapy, SCI medicine searches
yielded more results than a combined search of both SCI subfiles.
The scope and scientific relevance of the constructed SCI Medicine
section were on the whole quite acceptable. (Note: SCI-CLIN, SCI-BIOM
and further SCI subfiles edited by the publishers were discontinued,
e. g., at DIMDI, on I.01.2001).
The difference test for two ratios from
two large independent samples was used to examine SCI medicine
versus MEDLINE and SCI Medicine versus EMBASE. It was assumed that
each database constituted a large independent sample (with over
2 million records each for 1995 - 2000)
of all the internationally published medical articles. Such a statistical
test is valid only if the differences in language distribution are
not attributable to differences in subject concentrations or in
qualitative criteria.
Differences in scientific coverage were controlled by the composition
of the SCI Medicine segment. For the databases evaluated here, similar
qualitative parameters can be assumed (and should further be imputed)
in view of the decades long worldwide testing and usage of MEDLINE,
SCI and EMBASE by the scientific public. Detailed database descriptions
are available through DIMDI ([7]) and other hosts, DIALOG, STN Karlsruhe,
etc.)
Furthermore, the content overlap of non-English-language records
for combined databases (SCI Medicine+MEDLINE+EMBASE
for the year 2000) was determined. To do this, duplications of all
German, French, Japanese and Chinese documents retrievable in this
combined database (”superbase”)
were removed. During this procedure, the results of the SCI medicine
section remained unaffected. Next, additional results from MEDLINE
were obtained and finally the unique records present in EMBASE,
but absent from SCI Medicine and MEDLINE, were added Since this extremely
technical ’’duplicate checking’’ and
removing method ([7]) is quite (cpu) time consuming, documents published
in the year 2000 were evaluated as examples.
Results
Results
Country and Language Distribution in the JCR 1997 and
1998 (Science Editions)
Table [1] shows
the results on the origin of journals in the JCR 1998, arranged
according to frequency of publication country and classified according
to language (English or Multi-Language).
The corresponding list for the JCR 1997 showed - for a somewhat
smaller number of periodicals - similar ratios and is available
upon request. An average of 68 % of the JCR journals
for both volumes were published in three countries: the United States,
the United Kingdom and The Netherlands. If we include German and
Swiss publications, the percentage increases to almost 80 %.
Forty percent of the periodicals with an impact factor were published
in the United States alone.
Table 1 Periodicals
in Journal Citation Report 1998 ”Science Edition”:
Publishers’ Countries and Publication Languages.
|
Publishers’ Country
|
Number of Journals
|
% of the total of
Journals
in JCR
|
Journals classified English
|
ML1 *
- classified periodicals
|
English : ML
ratio
|
Corresponds to % Englisch
|
|
USA
|
2.110
|
38,6
|
2.033
|
77
|
26,4
|
94,4
|
|
UK
|
1.068
|
19,5
|
953
|
115
|
8,3
|
89,2
|
|
The Netherlands
|
535
|
9,8
|
422
|
113
|
3,7
|
78,9
|
|
Germany
|
408
|
7,5
|
255
|
153
|
1,7
|
62,5
|
|
Switzerland
|
173
|
3,2
|
123
|
50
|
2,5
|
71,1
|
|
France
|
165
|
3,0
|
88
|
77
|
1,1
|
53,3
|
|
Japan
|
141
|
2,6
|
115
|
26
|
4,4
|
81,6
|
|
Russia
|
112
|
2,0
|
112
|
0
|
112:0
|
100
|
|
Canada
|
77
|
1,4
|
30
|
47
|
0,6
|
39,0
|
|
Denmark
|
58
|
1,1
|
47
|
11
|
4,3
|
81,0
|
|
Australia
|
49
|
0,9
|
48
|
1
|
48,0
|
98,0
|
|
Italy
|
69
|
1,3
|
57
|
12
|
4,8
|
82,6
|
|
Sweden
|
38
|
0,7
|
30
|
8
|
3,8
|
79,0
|
|
...
|
|
|
|
|
|
|
|
China PR
|
31
|
0,6
|
29
|
2
|
14,5
|
93,5
|
|
Other countries
|
433
|
7,9
|
338
|
95
|
3,6
|
78,1
|
|
|
|
|
|
|
|
|
|
JCR, in toto
|
5.467
|
100
|
4.680
|
787
|
5,9
|
85,6
|
|
* ML = Multi-Language
|
In particular, the contributions of The Netherlands (about 10 %) and
Switzerland (over 3 %) proved the international
role of successful domestic publishing efforts in so-called smaller
countries.
Of the journals with impact factors of one or greater, i. e.,
journals in the top 35 % of the JCR, 51 % were
based in the United States, 21 % in the United
Kingdom and about 10 % in The Netherlands. Germany
was home to 6 % of this periodicals. Switzerland followed
with about 3 %; Denmark and France were next.
Where IF > = 1, it was found
that 89 % of the journals were classified as English. The top journals, whose IF > = 3,
had the following distribution for the years 1997 and 1998: United
States at 70.3 % and at 71 %,
United Kingdom at 19 % and 19.7 %,
Netherlands at 5.4 % and 6.3 % With
respect to this set of journals, 3.5 % and 3.4 % were
published in Germany for the same years. Following these countries
in the same IF range were Denmark, Switzerland and New Zealand.
The share of English-classified journals
with impact factors of 3 or more was 97 - 98 % for
each year (detailed tables available upon request).
In the JCR, the ratio of English to Multi-Language was 5.2 to 1 (83.9 % in
English) in 1997 and 5.9 to 1 (85.6 % in English)
in 1998. Table [1] shows that
in the publishing countries English-classified journals
prevailed. For France, the English/Multi-Language ratio
was close to one, likely attributable to policies promoting the
French language (1997: 75 to 78; 1998: 88 to 77). For the sequence
Germany (about 3 to 2), Switzerland, Netherlands, Japan and China,
this ratio increases quite markedly in favor of English. For journals
based in the Russian Federation, those classified exclusively as English obtained an impact factor.
Among the EU countries mentioned here, including Switzerland,
there were 3.2 English-designated journals
for every Multi-Language-designated journal
(1766 to 546) in the year 1997.
Canada was noteworthy in both years with an English/Multi-Language ratio
of about 1 to 1.5 (30 to 47 in the year 1998). This may have been
due mostly to the mixed-language publications (English and French).
JCR Languages and Impact Factor Intervals
Fig. [2] shows the number
of English and Multi-Language journals in
the JCR 1998 as a function of IF at intervals of 0.5. The central value
of the interval was chosen in each interval; for example, the interval
0.00 - 1.00 is represented in Fig. [2]
by the value 0.75. Both groups diminish
exponentially as the IF increases (logarithmic transformation of
these numbers yields straight lines). Hence, the number of Multi-Language journals approaches zero for
impact factors above three. This means that the most highly cited
journals, IF > = 3, were almost
exclusively classified as English.
Fig. 2 English-language and Multi-Language
Journals in JCR 1998 as a Function of Impact Factor Levels. X axis:
Impact Factor (Citation Frequency); Y axis: Number of Journals.
Blue dots: English; black dots: multi-language.
If the log of the English/Multi-Language ratio
is plotted against the impact factor, a nearly straight line with
a positive slope develops. This indicates that the citation frequency,
as calculated by ISI, grows exponentially with English-language
representation.
In the JCR 1997, the 4,963 journals (4166 English and
797 Multi-Language) listed exhibit similar
results (graphs available upon request).
Languages of Medical Journals in JCR
Table [2] illustrates that
the level of English classifications
for JCR 1998 periodicals depended on the discipline. In our constructed group
of medical and related journals, it was 93.4 %,
well above the average of 85.6 %.
Table 2 Periodicals ”Medicine
and Related Areas” included in Journal Citation Report/ Science
Edition 1998 (JCR): Ratios of Publication Languages English: Multi-Language
|
|
Number of Journals
|
English-classified Periodicals
(%)
|
ML-classified Periodicals (%)
|
Ratios
English :
ML
|
|
Medicine and Related Areas
|
2.191
|
2.001 (91,3 %)
|
190 (8,7 %)
|
10,5 : 1
|
|
Entire JCR for comparison
|
5.467
|
4.680 (85,6 %)
|
787 (14,4 %)
|
5,9 : 1
|
Publication Languages in Literature Databases
For the period 1995 - 2000, the SCI
indicated the greatest coverage with around 5.57 million documents,
95.5 % of which were indicated as English. MEDLINE indexed approximately
2.52 million publications during the same period; 88.5 % of
the documents were in English. In EMBASE, 89.8 % of
the 2.44 million articles were written in English. If one examined
the two periods 1995 - 1997 and 1998 - 2000
separately, similar values would be discovered in the three databases,
with a slight tendency in favour of the English language. When compared
to MEDLINE and EMBASE, the SCI showed the highest preference English-language
sources in the period 1995 - 2000; other
languages had representation below 5 %.
Medicine and Related Areas
MEDLINE and EMBASE database records (Table [3]) were compared with the entirety
of those SCI documents for the publication years 1995 - 2000
bearing subject codes (65) for Medicine and Related
Areas. In addition, the corresponding data from the SCI subfile
SCI-CLIN were included in the Table.
Table 3 Publication
Languages in Medicine and Relates Areas in the Period 1995 - 2000
in pertinent bibibliographic databases - with special emphasis
on the relevant parts of the Science Citation Index.
Number
of documented Publications1 (percentages in parentheses)
in the individual files
|
|
MEDLINE
|
EMBASE
|
SCI - Medicine2
|
SCI - CLIN3
|
|
English
|
2.226.324
|
(88.5 %)
|
2.177.085
|
(89.8 %)
|
2741.246
|
(95.3 %)
|
1.394.388
|
(94.5 %)
|
|
German
|
51.747
|
(2.1 %)
|
72.853
|
(3.0 %)
|
48.930
|
(1.7 %)
|
37.843
|
(2.6 %)
|
|
French
|
48.145
|
(1.9 %)
|
59.704
|
(2.5 %)
|
44.178
|
(1.5 %)
|
29.677
|
(2.0 %)
|
|
Japanese
|
42.894
|
(1.7 %)
|
38.161
|
(1.6 %)
|
3.185
|
(0.1 %)
|
1
|
(0 %)
|
|
Russian
|
38.981
|
(1.6 %)
|
1.640
|
(0.1 %)
|
15.019
|
(0.5 %)
|
4.280
|
(0.3 %)
|
|
Spanish
|
31.347
|
(1.2 %)
|
23.688
|
(1.0 %)
|
13.929
|
(0.5 %)
|
8.685
|
(0.6 %)
|
|
Chinese
|
11.388
|
(0.5 %)
|
8.012
|
(0.3 %)
|
2.211
|
(0.1 %)
|
2
|
(0 %)
|
|
Italian
|
13.960
|
(0.6 %)
|
13.647
|
(0.6 %)
|
1.810
|
(0.1 %)
|
0.6
|
(0 %)
|
|
Other
|
49.708
|
(2.0 %)
|
29.631
|
(1.2 %)
|
6.016
|
(0.2 %)
|
124
|
(0 %)
|
|
1= Number of records retrieved
by grips (7) commands in the combined data fields Publication Year
(PY) und Language (LA).
2=selected Journal Subject Codes (JSC (7)) ‚Medicine
and Related Fields‘
3= SCI segment Clinical Medicine compiled by ISI (Subfile
SF=CLIN in SCISEARCH at DIMDI (7) - in Jan 2001 no longer
continued )
|
For the period 1995 - 2000, MEDLINE
and EMBASE had about equal coverage, whereas the constructed SCI
Medicine segment contained about 15 % more documents.
Based on the more specific area definition, the ISI subfile SCI-CLIN
had less coverage than our SCI medicine segment.
The table further shows that both SCI Medicine and SCI-CLIN held
the largest share of English-language records with an average of
95 %. For the same period (1995 - 2000),
MEDLINE indexed some 3,000 more German-language publications than
the SCI Medicine segment; EMBASE indexed 24,000 more. MEDLINE included
4,000 more French-language articles than the SCI Medicine segment;
EMBASE had 15,500 more. Chinese and Japanese had negligeable shares
of 0.1 % in the SCI segments - compared to, e. g.,
1,7 % Japanese and 0.5 % Chinese
in MEDLINE.
The comparative evaluation of language shares from Table [3]
according to the difference
test for two ratios from two large independent samples yielded
highly significant differences for language distribution in SCI
Medicine versus MEDLINE and SCI Medicine versus EMBASE tests. For
example, the German language had a highly significant greater representation
in EMBASE than in the SCI Medicine segment. This was also true in
the EMBASE versus MEDLINE case.
For publications in German, French, Japanese and Chinese, which
were retrievable from a combined 2000 database incorporating SCI
Medicine, MEDLINE and EMBASE, there emerges - as Fig. [3]a illustrates - a similar picture
as in Table [3]. MEDLINE and,
in particular, EMBASE turned out to provide significantly more results
than the SCI Medicine segment for all four non-English publication
languages. Determination of the content overlap based
on SCI Medicine documents indicated that these records were clearly
enhanced by MEDLINE and especially EMBASE. Fig. [3]b shows 100 % of
the results for the three databases. The results from SCI Medicine
underlies the additional records from MEDLINE and EMBASE with their
stepwise organization. (Similar results related to the gross and overlap
contents biomedical databases we described in (23) from detailed
comparative searching in about 30 pertinent files).
Fig. 3 a. Gross
Database Yields
German-, French-, Japanese- and Chinese
Language Publication Referrals of Publication Year 2000 in the Science
Citation Index (SCI) Medicine segment (blue), in MEDLINE (ME) (grey)
and in EMBASE (EM) (white). X axis: German/ French/ Japanese/ Chinese;
Y axis: Number of publication referrrals in publication year 2000.
b. Content
Overlap of the individual publication
refererrals: supplementing the documents in SCI-Medicine first by
MEDLINE and then [SCI+MEDLINE] by EMBASE.
X axis: German/ French/ Japanese/ Chinese;
Y axis: Yield of publication referrals in 2000 (in Percent), composed
of 1. all pertinent SCI Medicine documents (blue), 2. additional
documents from MEDLINE (grey), and 3. unique EMBASE documents in
addition to the SCI+MEDLINE result (white)
[Composite result from SCI-Medicine + MEDLINE + EMBASE
taken as 100 %]
Discussion
Discussion
The results indicate that in the late nineties Anglo-American (58 %)
and Dutch (10 %) publishers dominated among journals with
impact factors. >From 7.5 % to 2.5 % of
the JCR journals were published, by order of importance, in Germany,
Switzerland, France and Japan.
According to the JCR language classifications - which must be considered
with some reservations - publishing in English favored a high IF
level and, therefore, a high international citation frequency.
Periodicals published solely in non-Roman alphabets have apparently
the lowest likelihood of obtaining an impact factor. According to
Table [1], all journals with
an impact factor published in Russia were classified as English by ISI. Table [2] would imply that the medical Multi-Language journals tend to be cited
less than the JCR average.
The data on publication languages in the JCR and in databases are
not comparable for two reasons: first, the language specifications
in the JCR refer to complete volumes of journals, whereas those
of literature databases refer to individual articles; secondly,
it was already pointed out that JCR journals classified as English may include a large portion of
original articles written in other languages, such as the Deutsche Medizinische Wochenschrift. Conversely,
a series of journals with predominantly English-language articles,
such as Experimental Brain Research,
was indexed in the JCR as Multi-Language.
By way of contrast, the literature databases classified each of
the articles from Exp Brain Res as English-language.
Approximately 85 % of the journals in the JCR
are classified as English. (If the set
is restricted to medical JCR journals, the share rises to 93.4 %.)
At first glance, the English-language records in the JCR command
a significantly lower share than in MEDLINE (89 %),
EMBASE (90 %) and especially the SCI (95 %)
and thus suggest that non-English JCR
journals could have a greater representation. Based on partially
unexplained language classifications in the JCR, a comparison of
the proportion of English-language representation is not possible.
However, on the databank level, one may compare the SCI - representing
the data basis of the JCR Science Editions - and its Medicine segment with MEDLINE and EMBASE.
It becomes apparent then that the SCI Medicine segment examined
here has a 15 %-larger scope than MEDLINE or EMBASE
and reflects the largest number of English-language sources.
Table [3] shows major differences
in the language distribution of individual databases. English-language
sources in the SCI Medicine segment have the highest representation
according to the difference test with
a high level of significance. On the other hand, all other publication
languages examined have a significantly higher frequency in MEDLINE
and EMBASE than in SCI Medicine. These statistics hold for the predictions
that, on the one hand, the tested medical databases may be viewed
as random samples from the (same) universe of international medical articles,
that secondly, subjects areas are comparable, and that no disparate
qualitative standards between these systems occur.
In the constructed SCI Medicine segment, coverage is quite identical
to that of MEDLINE/EMBASE. After decades long usage by
the scientific community, these products of ISI, NLM and Elsevier
appear qualitatively comparable.
The aforementioned high under-representation of non-English-language
records in the SCI and its Medicine segment is significant for the
impact factor, because the IF is calculated using cited references
from the 5,700 SCI source journals ([16]). These are the active citing journals selected by ISI for IF
determinations.
The preferred selection of English-language sources in medicine and
the natural sciences for the SCI shows up, therefore, in the citation
analysis of the JCR as an English-language
bias. Total cited references in, for example, non-SCI journals
publishing in German or French are not considered for the IF calculation. Thus,
the following speculative question seems justified: How did the
JCR change with the evaluation of additional cited references from
other relevant databases? For example, MEDLINE, EMBASE and BIOSIS
Previews (Biological Abstracts) include
no citation data in their bibliographic information ([21], [23]). In
the field of chemistry/ biochemistry, the Chemical Abstracts
Service at Columbus/ Ohio has begun in 2000 to store cited
references in CA/CA-plus databases.
In the area of emergency medicine, Barnaby and Gallagher ([2], [9]
) reported that the SCI-based JCR does not reflect the relevant
advancements in their field, since this discipline is not represented by
any citing journal for the IF calculation.
One must therefore suspect the presence of a bias during the IF
derivation. Any distinction between ’’actively
citing journals’’ and ’’only
cited journals’’ is technically without grounds.
The trauma surgeon Meenen ([18]) made similar claims and mentioned
the insufficient international visibility of important German-language
articles, for example on the method of osteosynthesis. This may
lead to omissions in applied therapy and, consequently, to disadvantages
for patients.
In light of the international significance of the Journal Impact Factors, these findings
overall suggest that it would be desirable if additional relevant
sources excluded by the SCI could be evaluated in calculating the
IF. In the area of medicine, such sources could be the MEDLINE and
EMBASE journals which the SCI does not cover.
Translation in English by M. Smith and E.
Garfield, Chairman Emeritus of ISI, for purposes of ASIS&T, SIG-Metrics.
Authorized by G. Winkmann (egwinkmann@aol.com), with kind assistance of Georg Thieme Verlag Stuttgart (volker.hirschel@thieme.de , andrea.hartmann@thieme.de).
