Slide de resumo

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Slide de resumo

• THE IMPACT FACTOR OF MEDICAL JOURNALS ITS USE
  AND MISUSE

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THE IMPACT FACTOR OF MEDICAL JOURNALS ITS USE
AND MISUSE

• Luis Benítez-Bribiesca
• Editor-in-Chief
• Archives of Medical Research
• (México)

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IMPACT FACTOR

• Counting references to rank the use of scientific
  journals was reported as early as 1927 by Gross
  and Gross. The term impact factor was not used
  until the publication of the 1961 in Science
  Citation Index (SCI) in 1963. This led to a
  byproduct, Journal Citation Reports (JCR), and a
  burgeoning literature using bibliometric
  measures.
• Source Garfield E. How can impact factors be
  improved? BMJ 1966 313413-5.

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IMPACT FACTOR

• The most used data in the JCR are impact
  factors-ratios obtained from dividing citations
  received in 1 year (numerator) by papers
  published during the two previous years
  (denominator). JCRs impact calculations are
  based on original research and review articles,
  as well as on notes. Letters of the type
  published in the BMJ and the Lancet are not
  included in the publication count, but all
  references are counted in the numerator.

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IMPACT FACTOR

• The scope of bibliometric studies is the
  treatment and quantitative analysis of scientific
  publications. They belong to the so-called
  social studies of science and science policy
  constitutes one of its main applied fields.

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JOURNALS WITH THE HIGHEST IMPACT FACTOR IN
1969Source Farfield E. Citation Analysis as a
Tool in Journal Evaluation. Science 1972
178471
ITEM 0001 0002 0003 0004 0005 0006 0007 0008 0009 0010 0011 0012 0013 0014 0015 CITED JOURNAL ACCOUNTS CHEM RES ADV PROTEIN CHEM PHARMACOL REV BACTERIOL REV ANNU REV BIOCHEM PHYSIOL REV SOLID STATE PHYS ADV ENZYMOL INT REV CYTOL J MOL BIOL REC PROG HORMONE RES P NAT ACAD SCI USA J EXP MED Q REV CHEM REV 1969 CITATION TO 1967 AND 1968 ARTICLES 820 184 448 804 932 572 228 192 144 7340 232 11548 2700 452 408 ARTICLES PUBLISHED IN 1967 AND 1968 28 8 20 39 53 33 14 20 16 833 27 1348 325 55 50 IMPACT FACTOR 29.285 23.000 23.400 20.615 17,584. 17.333 16.285 9.600 9.000 8.811 8.592 8.566 8.307 8.218 8.160
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JOURNALS WITH THE HIGHEST IMPACT FACTOR IN
1999Source Journal Citation Reports (JCR) on
CD-ROM 1999 Science Edition Journal
RankingsSorted by Impact Factor
RANK 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 JOURNAL ANNU REV IMMUNOL ANNU REV BIOCHEM CELL NAT GENET NATURE NEW ENGL J MED NAT MED ANNU REV CELL DEV BI CURR OPIN CELL BIOL SCIENCE PHYSIOL REV ANNU REV NEUROSCI CA-CANCER J CLIN CHEM REV ANNU REV PHARMACOL TOTAL CITES 11865 16683 159955 34030 303563 134065 20043 6170 11992 265921 11061 6824 2564 25361 4360 IMPACT FACTOR 47.564 37.111 36.242 30.693 29.491 28.857 26.584 26.263 25.631 24.595 23.953 22.605 22.327 21.244 21.175 ARTICLES 29 30 346 210 1016 380 165 24 91 971 32 21 18 113 18
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JOURNALS PUBLISHING REVIEW ARTICLES WITHINTHE
50 MOST CITED IN 1969 Source Garfield E.
Citation Analysis as a Tool in Journal
Evaluation. Science 1972 178471

ITEM 0001 0002 0003 0004 0005 0006 0007 0008 0009 JOURNAL PHARMACOL REV BACTERIOL REV PHYSIOL REV SOLID STATE PHYS Q REV CHEM REV ANNU REV PL PHYSIOL ANNU REV MICROBIOL BIOL REV 1969 CITATION TO 1967 AND 1968 ARTICLES 448 804 572 228 452 408 296 288 176 ARTICLES PUBLISHED IN 1967 AND 1968 20 39 33 14 55 50 42 44 34 IMPACT FACTOR 22.400 20.615 17.333 16.285 8.218 8.160 7.047 6.545 5.176
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JOURNALS PUBLISHING REVIEW ARTICLES WITHIN THE 50
MOST CITED IN 1999Source Journal of Citation
Reports (JCR) on CD-ROM 1999 Science Edition
Journal Rankings Sorted by Impact Factor.
RANK 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 JOURNAL ANNU REV IMMUNOL ANNU REV BIOCHEM ANNU REV CELL DEV BI CURR OPIN CELL BIOL PHYSIOL REV ANNU REV NEUROSCI CHEM REV ANNU REV PHARMACOL ENDOCR REV TRENDS NEUROSCI ANNU REV PHYSIOL ANNU REV PLANT PHYS PHARMACOL REV ANNU REV ASTRON ASTR CURR OPIN GENET DEV ANNU REV BIOPH BIOM CURR OPIN IMMUNOL TOTAL CITES 11865 16683 6170 11992 11061 6824 25361 4360 8308 14518 6416 6482 6512 3969 5893 3152 6264 IMPACT FACTOR 47.564 37.111 26.263 25.631 23.953 22.605 21.244 21.175 20.250 19.925 19.797 17.000 15.421 15.067 12.665 12.026 11.887 ARTICLES 29 30 24 91 32 21 113 18 32 64 35 25 18 14 91 14 92
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BIOMEDICAL JOURNALS WITH THE HIGHEST IMPACT
FACTOR (1999)Source Journal Citation Reports
(JCR) on CD-ROM 1999 Science Edition Journal
Rankings Sorted by Impact Factor
RANK 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 JOURNAL NAT MED J EXP MED J CLIN INVEST HUM GENE THER GENE THER LAB INVEST MOL MED TODAY CANCER GENE THER MOL MED J MOL MED-JMM P SOC EXP BIOL MED ANTISENSE NUCLEI A EXP HEMATOL VACCINE J HEMATOTH STEM CELL TOTAL CITES 20043 68208 81251 6449 4249 12017 929 866 1557 1572 7227 934 4227 6341 1035 IMPACT FACTOR 26.584 15.651 10.921 6.403 5.237 4.530 4.411 4.188 4.155 3.748 3.559 3.441 3.258 3.173 3.116 ARTICLES 165 132 374 253 237 171 61 62 68 123 121 65 196 544 31
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MEDICAL JOURNALS WITH THE HIGHEST IMPACT FACTOR
(1999)Source Journal Citation Reports (JCR) on
CD-ROM 1999 Science Edition Journal Rankings
Sorted by Impact Factor
RANK 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 JOURNAL NEW ENG J MED JAMA- J AM MED ASSOC LANCET ANN INTERN MED ANNU REV MED ARCH INTERN MED BRIT MED J AM J MED MEDICINE BRIT MED BULL J INVEST MED ANN MED AMYLOID CAN MED ASSOC J MED CLIN N AM TOTAL CITES 134065 64762 112952 36492 2426 20067 50603 21241 4425 2465 741 1811 358 4873 2149 IMPACT FACTOR 28.857 11.435 10.197 10.097 7.219 6.705 5.143 4.977 4.723 3.381 2.922 2.566 2.371 2.356 2.277 ARTICLES 380 364 1108 221 33 266 761 168 29 49 47 77 38 176 83
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THE USE OF IMPACT FACTOR

• The impact factor is being used with increasing
  frequency to evaluate the quality of a journal
  and the relevance of individual scientific
  output despite a number of articles and claims
  that challenge the use of this index as a sound
  criterion for judging the quality of both
  research and journals. It is frequently
  overlooked that Garfield himself, the inventor of
  the IF, emphasized that its potential value would
  be primarily in the management of library journal
  collections to determine their optimum makeup,
  providing solid basis for cost-benefit analysis
  of subscription budgets.

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THE USE OF IMPACT FACTOR

• The impact of the IF has been so great that its
  use has been injudiciously extended to judge the
  quality of a journal and what is more
  distressing, the quality of scientific output.
  Furthermore if the IF is taken as an indication
  for orienting editorial policies, then scientists
  and journals in peripheral fields would find
  increasing difficulties in publishing important
  contributions out of the mainstreams of current
  scientific research. In other words, this
  possesses the danger to halt scientific
  creativity and freedom.

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THE MISUSE OF IMPACT FACTOR

• Traditionally, committees formed by senior
  scientists scrutinize the scientific production
  of the candidate and mainly judge the quantity
  and quality of their publications. Quantity is
  easily evaluated, involving counting the number
  of articles, whereas quality is a notoriously
  difficult aspect to appraise, in that
  subjectivity and bias frequently overshadow the
  process.

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THE MISUSE OF IMPACT FACTOR

• Most evaluation committees in developing nations
  currently base promotions, resource allocations,
  and awards solely on citation indices and IF,
  particularly in the medical field. What is more
  surprising is that most scientists and peer
  reviewers seem to be convinced that this is the
  best method for considering scientific quality.

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THE MISUSE OF IMPACT FACTOR

• Hecht et al warn that IF should not be misused to
  evaluate journals or to validate scientific
  relevance, especially in decisions regarding
  employment, funding, and academic promotions.
  They emphasize that IF has clearly become a key
  marketing tool in biomedical publishing, and fear
  that editorial policies, once determined by
  scientific editors, may increasingly be dictated
  by executives and accountants.

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THE MISUSE OF IMPACT FACTOR

• Garfield points out that successful editors and
  publishers know that in order to improve the
  editorial quality of journals, there is no
  substitute for good judgment, quality, and
  relevance. Impact and other citation measures
  merely report the facts.

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PROBLEMS ASSOCIATED WITH THE USE JOURNAL IMPACT
FACTORS

• Journal impact factors are not statistically
  representative of individual journal articles.
• Journal impact factors correlate poorly with
  actual citations of individual articles.
• Review articles are heavily cited and inflate the
  impact factor of journals.
• Long articles collect many citations and yield
  high journal impact factors.
• Short publications lag allows many short-tem
  journal self-citations and produces a high
  journal impact factor.
• Citations in the national language of the journal
  are preferred by the journals authors.

• Database has an English language bias.
• The database is dominated by U.S. Publications.
• Impact factor depends on the dynamics (expansion
  or contraction) of the research field.
• Small research fields tend to lack journals with
  high impact.
• The citation of articles determines journal
  impact but not viceversa .
• Citation is biased when publications come from
  scientifically less developed countries. A good
  example is what occurs in Latin America.

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PROBLEMS ASSOCIATED WITH THE USE JOURNAL IMPACT
FACTOR

• Articles that came directly from Latin America in
  1995 represented only 1.8 of the total. Even so,
  this represents an increase from 1981, in which
  year the figure was 1.3. Another important
  finding was that 85 of the scientific articles
  originating in Latin America came from only four
  countries Brazil, Argentina, Mexico and Chile.
  These articles were cited between 40 and 60
  less than the world average for papers in the
  same field.

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LEADING LATIN AMERICAN NATIONS CITED IN THE
SCISource Ardila R. Scientific Publishing in
Latin America. Mexico (1999)
COUNTRY AVERAGE IMPACT FACTOR
BRAZIL 0.646
ARGENTINA 0.352
MEXICO 0.332
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CLINICAL MEDICINE AND EMERGING FIELDS

• There is a great difference in the numbers of
  citations between basic biomedical research and
  purely clinical publications. Biomedical
  research, particularly if releated to molecular
  genetics, tends to be highly cited, while
  clinical publications are not. Clinical medicine
  publications draw heavily on basic science
  references, but not viceversa.

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CLINICAL MEDICINE AND EMERGING FIELDS

• The goals of the scientist can be diverted from
  the original purpose of scientific endeavor
  towards achieving a higher citation rate,
  especially in the biomedical sciences. To obtain
  the benefits of funding and academic promotion,
  most medical scientists prefer to work in
  molecular genetics rather than to participate in
  patient-oriented research. This is contributing
  to the progressive decline of physician-scientists
  .

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AGONY OF IF. THE INTERNET

• The radical change brought about by the Web for
  publishing and searching scientific literature is
  changing the classical scheme of printed library
  collections and private journal subscriptions. It
  is, therefore, foreseeable that the IF will lose
  its significance to the extent that electronic
  publishing and free access to databases
  substitute for printed journals.