February 2009
Bibliometric Analysis
for the U.S. Environmental Protection Agency/Office of Research
and Development's Endocrine Disrupting Chemicals (EDCs)
Research Program
This is a bibliometric analysis of the papers prepared by intramural and extramural researchers
of the U.S. Environmental Protection Agency's (EPA) Endocrine Disrupting Chemicals
(EDCs) Research Program. For this analysis, 698 (652 journal articles and 46 non-journal
publications) were reviewed, and they were published from 1998 to 2008. The journal articles
were cited 12,895 times and the non-journal publications were cited 180 times in the journals
covered by Thomson's Web of Science1 and Scopus2. Of the 652 journal articles, 598 (91.7%)
have been cited at least once in a journal. Of the 46 non-journal publications, 20 (43.5%) have
been cited at least once in a journal.
Searches of Thomson Scientific's Web of Science and Elsevier's Scopus were conducted to
obtain times cited data for the EDCs journal publications. The analysis was completed using
Thomson's Essential Science Indicators (ESI) and Journal Citation Reports (JCR) as
benchmarks. ESI provides access to a unique and comprehensive compilation of essential
science performance statistics and science trends data derived from Thomson's databases. For
this analysis, the ESI highly cited papers thresholds as well as the hot papers thresholds were
used to assess the influence and impact of the EDCs papers. JCR is a recognized authority for
evaluating journals. It presents quantifiable statistical data that provide a systematic, objective
way to evaluate the world's leading journals and their impact and influence in the global
research community. The two key measures used in this analysis to assess the journals in
which the EPA EDCs papers are published are the Impact Factor and Immediacy Index. The
Impact Factor is a measure of the frequency with which the "average article" in a journal has
been cited in a particular year. The Impact Factor helps evaluate a journal's relative
importance, especially when compared to other journals in the same field. The Immediacy
Index is a measure of how quickly the "average article" in a journal is cited. This index
indicates how often articles published in a journal are cited within the same year and it is useful
in comparing how quickly journals are cited.
The report includes a summary of the results of the bibliometric analysis, an analysis of the 652
EDCs journal papers analyzed by ESI field (e.g., Environment/Ecology, Pharmacology &
Toxicology, Plant & Animal Science), an analysis of the journals in which the EDCs papers
were published, a table of the highly cited researchers in the EDCs Research Program, an
analysis of the non-journal publications, and any patents that have resulted from the program.
Thomson Scientific's Web of Science provides access to current and retrospective multidisciplinary information
from approximately 8,830 of the most prestigious, high impact research journals in the world. Web of Science also
provides cited reference searching.
2
Scopus is a large abstract and citation database of research literature and quality Web sources designed to support
the literature research process. Scopus offers access to 15,000 titles from 4,000 different publishers, more than
12,850 academic journals (including coverage of 535 Open Access journals, 750 conference proceedings, and 600
trade publications), 27 million abstracts, 245 million references, 200 million scientific Web pages, and 13 million
patent records.
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Bibliometric Analysis ofEDCs Research Program Journal Articles—February 2009
SUMMARY OF RESULTS
l. More than one-quarter of the EDCs publications are highly cited papers. 181 (27.8%) of
the EDCs papers qualify as highly cited when using the ES/ criteria for the top 10% of highly
cited publications. This is 2.8 times the 10% of papers expected to be highly cited. 27 (4.1%) of
the EDCs papers qualify as highly cited when using the ES/ criteria for the top 1 %, which is 4.1
times the number expected. 3 (0.5%) of these papers qualify as very highly cited when using the
criteria for the top 0.1%, which is 5 times the number anticipated. 2 (0.3%) papers actually meet
the 0.01 % threshold for the most highly cited papers, which is 30 times the expected number for
this program.
2. The EDCs papers are more highly cited than the average paper. Using the ESI average
citation rates for papers published by field as the benchmark, in 12 of the 16 fields in which the
562 EDCs journal papers were published, the ratio of actual to expected cites is greater than 1,
indicating that the EDCs papers are more highly cited than the average papers in those fields.
For all 16 fields combined, the ratio of total number of cites to the total number of expected cites
(12,895 to 6,667) is 1.9, indicating that the EDCs papers are more highly cited than the average
paper.
3. Nearly one-half of the EDCs papers are published in high impact journals ranked by
Impact Factor. 272 of the 652 papers were published in the top 10% of journals ranked by JCF?
Impact Factor, representing 41.7% of the EDCs journal papers. This number is 4.2 times higher
than the expected 65 papers. 184 of the 652 papers appear in the top 10% of journals ranked by
JCf? Immediacy Index, representing 28.2% of the EDCs journal papers. This number is 2.8 times
higher than the expected 65 papers.
4. Six of the EDCs journal papers qualify as hot papers. Using the hot paper thresholds
established by ESI as a benchmark, 6 hot papers, representing 0.9% of the EDCs papers, were
identified in the analysis. Hot papers are papers that were highly cited shortly after they were
published. The number of EDCs hot papers identified is 9 times higher than the expected 0.6 hot
papers.
5. The authors of the EDCs papers cite themselves much less than the average author. 544
of the 12,895 cites are author self-cites. This 4.2% author self-citation rate is well below the
accepted range of 10-30% author self-citation rate.
6. Twenty-one of the authors of the EDCs papers are included in ISIHighlyCited.com, which is
a database of the world's most influential researchers who have made key contributions to
science and technology during the period from 1981 to 1999.
7. No patents were issued and no patent applications were filed by investigators from 1997 to
2007 for research that was conducted under EPA's EDCs research program.
8. The 46 nonjournal publications were cited 180 times in journals. 20 (43.5%) were cited at least once
in a journal and the authors cited themselves 9 times (5.0% self-citation rate), which is much less than the
literature-reported 10-30% range for author self-citation. 2(4.4%) of the nonjournal publications were
highly cited when using the ESI criteria for the top 10% of highly cited publications.
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Bibliometric Analysis ofEDCs Research Program Journal Articles—February 2009
Highly Cited EDCs Publications
All of the journals covered by ESI are assigned a field, and to compensate for varying citation rates
across scientific fields, different thresholds are applied to each field. Thresholds are set to select
highly cited papers to be listed in ESI. Different thresholds are set for both field and year of
publication. Setting different thresholds for each year allows comparable representation for older and
younger papers for each field.
The 652 EDCs research papers reviewed for this analysis were published in journals that were assigned
to 16 of the 22 ESI fields. The distribution of the papers among these 16 fields and the number of
citations by field are presented in Table 1.
Tablet. EDCs Papers by ESI Fields
ESI Field
Agricultural Sciences
Biology & Biochemistry
Chemistry
Clinical Medicine
Computer Science
Engineering
Environment/Ecology
Geosciences
Mathematics
Microbiology
Molecular Biology & Genetics
Multidisciplinary
Neuroscience & Behavior
Pharmacology & Toxicology
Plant & Animal Science
Social Sciences, general
No. of Citations
26
1,390
398
1,626
3
29
3,362
7
0
1
64
1,100
274
3,582
1,007
26
Total = 12,895
No. of EPA Papers
3
79
36
74
2
5
195
1
1
1
7
10
26
138
72
2
Total = 652
Average Cites/Paper
8.7
17.6
11.0
22.0
1.5
5.8
17.2
7.0
0
1.0
9.1
110.0
10.5
26.0
14.0
13.0
19.8
There are 181 (27.8% of the papers analyzed) highly cited EPA EDCs papers in 12 of the 16 fields—
Agricultural Sciences, Biology & Biochemistry, Chemistry, Clinical Medicine, Computer Science,
Engineering, Environment/Ecology, Multidisciplinary, Neuroscience & Behavior, Pharmacology &
Toxicology, Plant & Animal Science, and Social Sciences—when using the ESI criteria for the top
10% of papers. Table 2 shows the number of EPA papers in those 12 fields that meet the top 10%
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Bibliometric Analysis ofEDCs Research Program Journal Articles—February 2009
threshold in ESI Twenty-seven (4.1%) of the papers analyzed qualify as highly cited when using the
ESI criteria for the top 1% of papers. These papers cover 6 fields—Biology & Biochemistry, Clinical
Medicine, Engineering, Environment/Ecology, Multidisciplinary, and Pharmacology & Toxicology.
Table 3 shows the 27 papers by field that meet the top 1% threshold in ESI The citations for these
27 papers are provided in Tables 4 through 9. There were 3 (0.5%) very highly cited EDCs papers in
the fields of Environment/Ecology and Multidisciplinary (see Table 10). These papers, which met the
top 0.1% threshold in ESI, are listed in Table 11. Two (0.3%) of the EDCs papers met the top
0.01% threshold in ESI (see Table 12), which is 30 times the expected number of papers that should
meet this threshold for this size program. These papers are listed in Table 13.
Table 2. Number of Highly Cited EDCs Papers by Field (top 10%)
ESI Field
Agricultural Sciences
Biology & Biochemistry
Chemistry
Clinical Medicine
Computer Science
Engineering
Environment/Ecology
Multidisciplinary
Neuroscience & Behavior
Pharmacology & Toxicology
Plant & Animal Science
Social Sciences, general
No. of Citations
21
506
183
940
3
24
2,077
1,080
11
2,539
779
17
Total = 8,180
No. of Papers
1
16
5
21
1
2
56
7
1
44
26
1
Total = 181
Average Cites/Paper
21.0
31.6
36.6
44.8
3.0
12.0
37.1
154.3
11.0
57.7
30.0
17.0
45.2
% of Papers in Field
33.3%
20.2%
13.9%
28.4%
50.0%
40.0%
28.7%
70.0%
3.8%
31.9%
36.1%
50.0%
27.8%
Table 3. Number of Highly Cited EDCs Papers by Field (top 1%)
ESI Field
Biology & Biochemistry
Clinical Medicine
Engineering
Environment/Ecology
Multidisciplinary
No. of
Citations
47
213
22
632
1,027
No. of
Papers
1
4
1
9
6
Average
Cites/Paper
47.0
53.2
22.0
70.2
171.2
% of EPA
Papers in
Field
1.3%
5.4%
20.0%
4.6%
60.0%
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Bibliometric Analysis ofEDCs Research Program Journal Articles—February 2009
ESI Field
Pharmacology & Toxicology
No. of
Citations
841
Total =
2,782
No. of
Papers
6
Total =
27
Average
Cites/Paper
140.2
103.0
% of EPA
Papers in
Field
4.4%
4.1%
Table 4. Highly Cited EDCs Papers in the Field of Biology & Biochemistry (top 1%)
No. of
Cites
47
First Author
Anway MD
Paper
Epigenetic transgenerational actions of endocrine disrupters.
Endocrinology 2006; 147(6): S43-S49.
Table 5. Highly Cited EDCs Papers in the Field of Clinical Medicine (top 1%)
No. of
Cites
151
48
6
8
First Author
Gray LE
Gray LE
Euling SY
Rider CV
Paper
Effects of environmental antiandrogens on reproductive development
in experimental animals. Human Reproduction Update 2001;7(3):248-
264.
Adverse effects of environmental antiandrogens and androgens on
reproductive development in mammals. InternationalJournal of
Andrology 2006;29(1):96-104.
Examination of US puberty-timing data from 1940 to 1994 for secular
trends: Panel findings. Pediatrics 2008;121:S172-S191.
A mixture of seven antiandrogens induces reproductive malformations
in rats. International Journal of Andrology 2008;3 1(2):249-262.
Table 6. Highly Cited EDCs Papers in the Field of Engineering (top 1%)
No. of
Cites
22
First Author
De Jesus MA
Paper
Nanofabrication of densely packed metal -polymer arrays for surface-
enhanced Raman spectrometry. Applied Spectroscopy
2005;59(12):1501-1508.
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Bibliometric Analysis ofEDCs Research Program Journal Articles—February 2009
Table 7. Highly Cited EDCs Papers in the Field of Environment/Ecology (top 1%)
No. of
Cites
187
130
48
186
18
18
26
5
14
First Author
Crisp TM
Ankley GT
Mills LJ
Swan SH
LeBlanc GA
Villeneuve DL
Mergler D
Kostich MS
Lorber M
Paper
Environmental endocrine disruption: an effects assessment and
analysis. Environmental Health Perspectives 1998;106(Suppl 1):11-
56.
Description and evaluation of a short-term reproduction test with the
fathead minnow (Pimephales promelas). Environmental Toxicology
and Chemistry 2001 ;20(6): 1276-1290.
Review of evidence: are endocrine-disrupting chemicals in the aquatic
environment impacting fish populations? Science of the Total
Environment 2005;343(l-3): 1-34.
Decrease in anogenital distance among male infants with prenatal
phthalate exposure. Environmental Health Perspectives
2005;113(8):1056-1061.
Crustacean endocrine toxicology: a review. Ecotoxicology
2007;16(1):61-81.
A graphical systems model to facilitate hypothesis-driven
ecotoxicogenomics research on the teleost brain-pituitary-gonadal axis.
Environmental Science & Technology 2007;41(1):321-330.
Methylmercury exposure and health effects in humans: a worldwide
concern. Ambio 2007;36(1):3-11.
Risks to aquatic organisms posed by human pharmaceutical use.
Science of the Total Environment 2008;389(2-3):329-339.
Exposure of Americans to polybrominated diphenyl ethers. Journal of
Exposure Science and Environmental Epidemiology 2008;18(1):2-19.
Table 8. Highly Cited EDCs Papers in the Field of Multidisciplinary (top 1%)
No. of
Cites
First Author
Paper
160
Hawkins MB
Identification of a third distinct estrogen receptor and reclassification
of estrogen receptors in teleosts. Proceedings of the National
Academy of Sciences of the United States of America 2000;97(20):
10751-10756.
248
ZhuY
Cloning, expression, and characterization of a membrane progestin
receptor and evidence it is an intermediary in meiotic maturation of
fish oocytes. Proceedings of the National Academy of Sciences of the
United States of America 2003; 100(5):2231-2236.
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Bibliometric Analysis ofEDCs Research Program Journal Articles—February 2009
No. of
Cites
252
69
259
39
First Author
ZhuY
Timms BG
Anway MD
KiddKA
Paper
Identification, classification, and partial characterization of genes in
humans and other vertebrates homologous to a fish membrane
progestin receptor. Proceedings of the National Academy of Sciences
of the United States of America 2003;100(5):2237-2242.
Estrogenic chemicals in plastic and oral contraceptives disrupt
development of the fetal mouse prostate and urethra. Proceedings of
the National Academy of Sciences of the United States of America
2005;102(19):7014-7019.
Epigenetic transgenerational actions of endocrine disrupters and mate
fertility. Science 2005;308(5727): 1466-1469.
Collapse of a fish population after exposure to a synthetic estrogen.
Proceedings of the National Academy of Sciences of the United States
o/^iwenca2007;104(21):8897-8901.
Table 9. Highly Cited EDCs Papers in the Field of Pharmacology & Toxicology (top 1%)
No. of
Cites
195
209
217
126
89
5
First Author
Parks LG
Laws SC
Gray LE
Zhou T
Wilson VS
Richardson VM
Paper
The plasticizer diethylhexyl phthalate induces malformations by
decreasing fetal testosterone synthesis during sexual differentiation in
the male rat. Toxicological Sciences 2000;58(2):339-349.
Estrogenic activity of octylphenol, nonylphenol, bisphenol A and
methoxychlor in rats. Toxicological Sciences 2000;54(1): 154-167.
Perinatal exposure to the phthalates DEHP, BBP, and DINP, but not
DEP, BMP, or DOTP, alters sexual differentiation of the male rat.
Toxicological Sciences 2000;58(2):350-365.
Developmental exposure to brominated diphenyl ethers results in
thyroid hormone disruption. Toxicological Sciences 2002;66(1): 105-
116.
Phthalate ester-induced gubernacular lesions are associated with
reduced ins!3 gene expression in the fetal rat testis. Toxicology Letters
2004;146(3):207-215.
Possible mechanisms of thyroid hormone disruption in mice by BDE
47, a major polybrominated diphenyl ether congener. Toxicology and
Applied Pharmacology 2008 ;226(3) : 244-25 0 .
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Bibliometric Analysis ofEDCs Research Program Journal Articles—February 2009
Table 10. Number of Very Highly Cited EDCs Papers by Field (top 0.1%)
ESI Field
Environment/Ecology
Multidisciplinary
No. of
Citations
200
259
Total =
459
No. of
Papers
2
1
Total =
3
Average
Cites/Paper
100.0
259.0
153.0
% of EPA
Papers in
Field
1.0%
10.0%
0.5%
Table 11. Very Highly Cited EDCs Papers (top 0.1%)
ESI Field
Environment/
Ecology
Multidisciplinary
No. of
Cites
186
14
259
First Author
Swan SH
Lorber M
Anway MD
Paper
Decrease in anogenital distance among male infants with
prenatal phthalate exposure. Environmental Health Perspectives
2005;113(8):1056-1061.
Exposure of Americans to polybrominated diphenyl ethers.
Journal of Exposure Science and Environmental Epidemiology
2008;18(1):2-19.
Epigenetic transgenerational actions of endocrine disrupters and
mate fertility. Science 2005;308(5727): 1466-1469.
Table 12. Number of Extremely Highly Cited EDCs Papers by Field (top 0.01%)
ESI Field
Environment/Ecology
Multidisciplinary
No. of
Citations
14
259
Total =
273
No. of
Papers
1
1
Total =
2
Average
Cites/Paper
14.0
259.0
136.5
% of EPA
Papers in
Field
0.5%
10.0%
0.3%
Table 13. Extremely Hi
ESI Field
Environment/
Ecology
No. of
Cites
14
First Author
Lorber M
ghly Cited EDCs Papers (top 0.01%)
Paper
Exposure of Americans to polybrominated diphenyl ethers.
Journal of Exposure Science and Environmental Epidemiology
2008;18(1):2-19.
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Bibliometric Analysis ofEDCs Research Program Journal Articles—February 2009
ESI Field
Multidisciplinary
No. of
Cites
259
First Author
Anway MD
Paper
Epigenetic transgenerational actions of endocrine disrupters and
mate fertility. Science 2005;308(5727): 1466-1469.
Ratio of Actual Cites to Expected Citation Rates
The expected citation rate is the average number of cites that a paper published in the same journal in
the same year and of the same document type (article, review, editorial, etc.) has received from the
year of publication to the present. Using the ESI average citation rates for papers published by field as
the benchmark, in 12 of the 16 fields in which the EPA EDCs papers were published, the ratio of
actual to expected cites is greater than 1, indicating that the EDCs papers are more highly cited than
the average papers in those fields (see Table 14). For all 16 fields combined, the ratio of total number
of cites to the total number of expected cites (12,895 to 6,667) is 1.9, indicating that the EDCs papers
are more highly cited than the average paper.
Table 14. Ratio of Actual Cites to Expected Cites for EDCs Papers by Field
ESI Field
Agricultural Sciences
Biology & Biochemistry
Chemistry
Clinical Medicine
Computer Science
Engineering
Environment/Ecology
Geosciences
Mathematics
Microbiology
Molecular Biology & Genetics
Multidisciplinary
Neuroscience & Behavior
Pharmacology & Toxicology
Plant & Animal Science
Social Sciences, general
TOTAL
Total
Cites
26
1,390
398
1,626
3
29
3,362
7
0
1
64
1,100
274
3,582
1,007
26
12,895
Expected Cite
Rate
15
1,164
292
922
1
13
1,622
6
0.1
3
130
48
456
1,507
480
8
6,667
Ratio
1.7
1.2
1.4
1.8
3.0
2.2
2.1
1.2
0
0.3
0.5
22.9
0.6
2.4
2.1
3.2
1.9
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Bibliometric Analysis ofEDCs Research Program Journal Articles—February 2009
JCR Benchmarks
Impact Factor. The JCR Impact Factor is a well known metric in citation analysis. It is a measure of
the frequency with which the "average article" in a journal has been cited in a particular year. The
Impact Factor helps evaluate a journal's relative importance, especially when compared to others in the
same field. The Impact Factor is calculated by dividing the number of citations in the current year to
articles published in the 2 previous years by the total number of articles published in the 2 previous
years.
Table 15 indicates the number ofEDCs papers published in the top 10% of journals, based on the JCR
Impact Factor. Two hundred seventy-two (272) of 652 papers were published in the top 10% of
journals, representing 41.7% of EPA's EDCs papers. This indicates that nearly one-half of the EDCs
papers are published in the highest quality journals as determined by the JCR Impact Factor, which is
4.2 times higher than the expected percentage.
Table 15. EDCs Papers in Top 10% of Journals by JCR Impact Factor
EPA EDCs
Papers in
that Journal
1
1
1
6
1
1
1
1
1
41
1
7
1
3
1
15
1
13
Journal
New England Journal of Medicine
Science
British Medical Journal
Proceedings of the National Academy of Sciences of the
United States of America
Cancer Research
Development
Human Reproduction Update
Nucleic Acids Research
Hippocampus
Environmental Health Perspectives
Journal of Clinical Endocrinology and Metabolism
Analytical Chemistry
American Journal of Epidemiology
Epidemiology
Molecular Ecology
Critical Reviews in Toxicology
Lab on a Chip
Endocrinology
Impact
Factor
(IF)
52.589
26.372
9.723
9.598
7.672
7.293
7.257
6.954
5.745
5.636
5.493
5.287
5.285
5.283
5.169
5.145
5.068
5.045
JCR IF
Rank
2
14
109
114
164
182
185
194
272
279
290
309
310
311
326
330
335
339
10
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Bibliometric Analysis ofEDCs Research Program Journal Articles—February 2009
EPA EDCs
Papers in
that Journal
2
1
1
1
4
1
22
1
1
2
9
87
1
1
19
1
1
1
1
4
2
1
3
1
1
3
3
Total = 272
Journal
Bioinformatics
Journal of Medicinal Chemistry
Cancer Epidemiology Biomarkers & Prevention
Cancer
Pediatrics
Tissue Engineering
Environmental Science & Technology
BMC Genomics
Applied and Environmental Microbiology
Environmental Science and Pollution Research
Toxicology and Applied Pharmacology
Toxicological Sciences
Evolution & Development
European Journal of Neuroscience
Biology of Reproduction
Journal of Chromatography A
American Journal of Public Health
Electrophoresis
Journal of Raman Spectroscopy
Chemical Research in Toxicology
BMC Bioinformatics
Physiological Genomics
Hormones and Behavior
Neuroscience
ATLA-Alternatives to Laboratory Animals
Analytica Chimica Acta
Fertility and Sterility
Impact
Factor
(IF)
5.039
4.895
4.642
4.632
4.473
4.409
4.363
4.180
4.004
3.894
3.846
3.814
3.733
3.673
3.670
3.641
3.612
3.609
3.514
3.508
3.493
3.493
3.401
3.352
3.203
3.186
3.168
JCR IF
Rank
340
359
405
408
435
456
465
514
571
598
614
622
659
680
682
695
709
710
744
745
756
756
782
815
871
877
883
11
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Bibliometric Analysis ofEDCs Research Program Journal Articles—February 2009
Immediacy Index. The JCR Immediacy Index is a measure of how quickly the average article in a
journal is cited. It indicates how often articles published in a journal are cited within the year they are
published. The Immediacy Index is calculated by dividing the number of citations to articles published
in a given year by the number of articles published in that year.
Table 16 indicates the number ofEDCs papers published in the top 10% of journals, based on the JCR
Immediacy Index. One hundred eighty-four (184) of the 652 journal articles appear in the top 10% of
journals, representing 28.2% of the EDCs papers. This indicates that more than one-quarter of the
EDCs papers are published in the highest quality journals as determined by the JCR Immediacy Index,
which is 2.8 times higher than the expected percentage.
Table 16. EDCs Papers in Top 10% of Journals by JCR Immediacy Index
EPA EDCs
Papers in that
Journal
1
1
1
6
3
2
1
1
1
1
1
1
13
1
2
1
41
7
2
1
Journal
New England Journal of Medicine
Science
British Medical Journal
Proceedings of the National Academy of Sciences of the
United States of America
Epidemiology
ILAR Journal
Nucleic Acids Research
Development
American Journal of Public Health
Human Reproduction Update
Lab on a Chip
Journal of Clinical Endocrinology and Metabolism
Endocrinology
Cancer Research
Environmental Science and Pollution
American Journal of Epidemiology
Environmental Health Perspectives
Analytical Chemistry
Reviews of Environmental Contamination and Toxicology
Cancer
Immediacy
Index
(II)
11.962
6.387
6.210
1.724
1.623
1.594
1.589
1.462
1.337
1.319
1.241
1.221
1.137
1.131
1.120
1.087
0.958
0.911
0.857
0.824
JCR 11
Rank
2
15
18
136
152
159
160
194
226
231
265
271
299
304
311
329
425
471
527
554
12
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Bibliometric Analysis ofEDCs Research Program Journal Articles—February 2009
EPA EDCs
Papers in that
Journal
4
1
1
1
1
1
1
19
1
1
1
4
3
1
2
3
1
1
9
1
16
1
22
Total = 184
Journal
Pediatrics
Journal of Medicinal Chemistry
Ambio
Journal of Environmental Monitoring
Experimental Gerontology
Molecular Ecology
Evolution & Development
Biology of Reproduction
Journal of Experimental Biology
Cancer Epidemiology Biomarkers & Prevention
Physiological Genomics
Environmental Pollution
Fertility and Sterility
Reproduction Fertility and Development
Molecular and Cellular Endocrinology
SAR and QSAR in Environmental Research
Molecular Reproduction and Development
Hippocampus
Reproductive Toxicology
Environment International
Environmental Research
Neuroscience
Environmental Science & Technology
Immediacy
Index
(II)
0.820
0.789
0.777
0.763
0.761
0.732
0.731
0.723
0.722
0.705
0.705
0.699
0.694
0.686
0.682
0.674
0.670
0.655
0.655
0.639
0.632
0.627
0.615
JCRll
Rank
557
594
610
625
626
663
665
675
678
702
702
716
726
739
746
765
771
800
800
834
845
856
876
Hot Papers
ESI establishes citation thresholds for hot papers, which are selected from the highly cited papers in
different fields, but the time frame for citing and cited papers is much shorter—papers must be cited
within 2 years of publication and the citations must occur in a 2-month time period. Papers are
assigned to 2-month periods and thresholds are set for each period and field to select 0.1% of papers.
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Bibliometric Analysis ofEDCs Research Program Journal Articles—February 2009
Using the hot paper thresholds established by ESI as a benchmark, 6 hot papers, representing 0.9% of
the EDCs papers, were identified in three fields—Environment/Ecology, Multidisciplinary, and
Pharmacology & Toxicology. The number ofEDCs hot papers is 9 times higher than expected. The
hot papers are listed in Table 17.
Table 17. Hot Papers Identified Using ESI Thresholds
Field
Environment/
Ecology
Multidisciplinary
Pharmacology &
Toxicology
ESI Hot
Papers
Threshold
3
6
6
10
10
3
No. of Cites
in 2-Month
Period
6 cites in
February-
March 2007
6 cites in
September-
October 2008
12 cites in
February-
March 2006
19 cites in
May-June
2006
10 cites in
February-
March 2004
3 cites in
January 2006
Paper
LeBlanc GA. Crustacean endocrine toxicology: a review.
Ecotox/co/ogy2007;16(l):61-81.
Lorber M. Exposure of Americans to polybrominated
diphenyl ethers. Journal of Exposure Science and
Environmental Epidemiology 2008;18(1):2-19.
Swan SH, et al. Decrease in anogenital distance among
male infants with prenatal phthalate exposure.
Environmental Health Perspectives 2005;! 13(8): 1056-1061.
Anway MD, et al. Epigenetic transgenerational actions of
endocrine disrupters and male fertility. Science
2005;308(5727): 1466-1469.
Zhu Y, et al. Cloning, expression, and characterization of a
membrane progestin receptor and evidence it is an
intermediary in meiotic maturation offish oocytes.
Proceedings of the National Academy of Sciences of the
United States of America 2003; 100(5):223 1-2236.
Carmichael NG, et al. Agricultural chemical safety
assessment: a multisector approach to the modernization of
human safety requirements. Critical Reviews in Toxicology
2006;36(l):l-7.
Author Self-Citation
Self-citations are journal article references to articles from that same author (i.e., the first author).
Because higher author self-citation rates can inflate the number of citations, the author self-citation rate
was calculated for the EDCs papers. Of the 12,895 total cites, 544 are author self-cites—a 4.2% author
self-citation rate. Garfield and Sher3 found that authors working in research-based disciplines tend to
cite themselves on the average of 20% of the time. MacRoberts and MacRoberts4 claim that
approximately 10% to 30% of all the citations listed fall into the category of author self-citation.
3 Garfield E, Sher IH. New factors in the evaluation of scientific literature through citation indexing. American
Documentation 1963;18(July):195-210.
4 MacRoberts MH, MacRoberts BR. Problems of citation analysis: a critical review. Journal of the American Society of
Information Science 1989;40(5):342-349.
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Bibliometric Analysis ofEDCs Research Program Journal Articles—February 2009
Kovacic and Misak5 recently reported a 20% author self-citation rate for medical literature. Therefore,
the 4.2% self-cite rate for the EDCs papers is well below the range for author self-citation.
Highly Cited Researchers
A search of Thomson's ISIHighlyCited. com revealed that 21 (1.5%) of the 1,379 authors of the EDCs
papers are highly cited researchers. ISIHighlyCited.com is a database of the world's most influential
researchers who have made key contributions to science and technology during the period from 1981
to 1999. The highly cited researchers identified during this analysis of the EDCs publications are
presented in Table 18.
Table 18. Highly Cited Researchers Authoring EDCs Publications
Highly Cited
Researcher
Andersen, Melvin E.
Ankley, Gerald
Birnbaum, Linda S.
Boobis, Alan R.
Brown, Sandra
Burger, Joanna
German, J. Bruce
Giesy, John P.
Guillette, Louis J.
Jobling, Susan
Klaassen, Curtis D.
McLachlan, John A.
Needham, Larry L.
Rao, P. Suresh
Chandra
Sih, Andrew
Soto, Ana M.
Starfield, Barbara
Stegeman, John J.
Affiliation
CUT Centers for Health Research
U.S. Environmental Protection
Agency
U.S. Environmental Protection
Agency
Imperial College London
Winrock International
Rutgers University
University of California-Davis
University of Saskatchewan
University of Florida
University of Brunei
University of Kansas Medical Center
Tulane University
National Center for Environmental
Health
Purdue University
University of California-Davis
Tufts University
The Johns Hopkins University
Woods Hole Oceanographic
Institution
ESI Field
Pharmacology
Environment/Ecology
Pharmacology
Pharmacology
Environment/Ecology
Environment/Ecology
Agricultural Sciences
Environment/Ecology
Environment/Ecology
Environment/Ecology
Pharmacology
Environment/Ecology
Environment/Ecology
Environment/Ecology
Environment/Ecology
Environment/Ecology
Pharmacology
Social Sciences, general
Pharmacology
Kavaci N, Misak A. Author self-citation in medical literature. Canadian Medical Association Journal
2004;170(13):1929-1930.
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Bibliometric Analysis ofEDCs Research Program Journal Articles—February 2009
Highly Cited
Researcher
Suidan, Makram T.
Sumpter, John P.
Wright, S. Joseph
Total = 21
Affiliation
University of Cincinnati
Brunei University
Smithsonian Tropical Research
Institute
ESI Field
Environment/Ecology
Environment/Ecology
Environment/Ecology
Patents
No patents have been issued or patent applications filed by investigators from 1998 to 2008 for
research that was conducted under EPA's EDCs Research Program.
Nonjournal Publications (Books, Book Chapters, Reports, and Proceedings)
Forty-six nonjournal publications (books, book chapters, reports, and proceedings) produced by the
program from 1998 to 2008 were included in the analysis. Of these 46 nonjournal publications, 20
(43.5%) have been cited at least once in a journal. The 46 publications were cited 180 times in the
journals covered by Thomson Reuter's 757 Web of Science. The authors of the nonjournal publications
cited themselves 9 times, a 5.0% self citation rate, which is well below the 10-30% range report in the
literature for author self-citation. Application of the ESI fields and highly cited benchmarks used for
journal papers to the nonjournal publications, indicated that 2 (4.4%) of the nonjournal publications
were highly cited when using the ESI criteria for the top 10% of highly cited publications. None of the
nonjournal publications met the ESI criteria for the top 1%, 0.1%, or 0.01% highly cited publications.
This bibliometric analysis was prepared by
Beverly Campbell of The Scientific Consulting Group, Inc.
in Gaithersburg, Maryland
under EPA Contract No. EP-C-05-015
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