Conflicts of interest at medical journals

the influence of industry-supported randomised trials on journal impact factors and revenue - cohort study

Andreas Lundh, Marija Barbateskovic, Asbjørn Hróbjartsson, Peter C Gøtzsche

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

Resumé

BACKGROUND: transparency in reporting of conflict of interest is an increasingly important aspect of publication in medical journals. Publication of large industry-supported trials may generate many citations and journal income through reprint sales and thereby be a source of conflicts of interest for journals. We investigated industry-supported trials' influence on journal impact factors and revenue.

METHODS AND FINDINGS: we sampled six major medical journals (Annals of Internal Medicine, Archives of Internal Medicine, BMJ, JAMA, The Lancet, and New England Journal of Medicine [NEJM]). For each journal, we identified randomised trials published in 1996-1997 and 2005-2006 using PubMed, and categorized the type of financial support. Using Web of Science, we investigated citations of industry-supported trials and the influence on journal impact factors over a ten-year period. We contacted journal editors and retrieved tax information on income from industry sources. The proportion of trials with sole industry support varied between journals, from 7% in BMJ to 32% in NEJM in 2005-2006. Industry-supported trials were more frequently cited than trials with other types of support, and omitting them from the impact factor calculation decreased journal impact factors. The decrease varied considerably between journals, with 1% for BMJ to 15% for NEJM in 2007. For the two journals disclosing data, income from the sales of reprints contributed to 3% and 41% of the total income for BMJ and The Lancet in 2005-2006.

CONCLUSIONS: publication of industry-supported trials was associated with an increase in journal impact factors. Sales of reprints may provide a substantial income. We suggest that journals disclose financial information in the same way that they require them from their authors, so that readers can assess the potential effect of different types of papers on journals' revenue and impact.

OriginalsprogEngelsk
TidsskriftP L o S Medicine
Vol/bind7
Udgave nummer10
Sider (fra-til)e1000354
ISSN1549-1277
DOI
StatusUdgivet - 26. okt. 2010

Fingeraftryk

Journal Impact Factor
Conflict of Interest
Cohort Studies
New England
Publications
Medicine
Internal Medicine
PubMed

Citer dette

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title = "Conflicts of interest at medical journals: the influence of industry-supported randomised trials on journal impact factors and revenue - cohort study",
abstract = "BACKGROUND: transparency in reporting of conflict of interest is an increasingly important aspect of publication in medical journals. Publication of large industry-supported trials may generate many citations and journal income through reprint sales and thereby be a source of conflicts of interest for journals. We investigated industry-supported trials' influence on journal impact factors and revenue.METHODS AND FINDINGS: we sampled six major medical journals (Annals of Internal Medicine, Archives of Internal Medicine, BMJ, JAMA, The Lancet, and New England Journal of Medicine [NEJM]). For each journal, we identified randomised trials published in 1996-1997 and 2005-2006 using PubMed, and categorized the type of financial support. Using Web of Science, we investigated citations of industry-supported trials and the influence on journal impact factors over a ten-year period. We contacted journal editors and retrieved tax information on income from industry sources. The proportion of trials with sole industry support varied between journals, from 7{\%} in BMJ to 32{\%} in NEJM in 2005-2006. Industry-supported trials were more frequently cited than trials with other types of support, and omitting them from the impact factor calculation decreased journal impact factors. The decrease varied considerably between journals, with 1{\%} for BMJ to 15{\%} for NEJM in 2007. For the two journals disclosing data, income from the sales of reprints contributed to 3{\%} and 41{\%} of the total income for BMJ and The Lancet in 2005-2006.CONCLUSIONS: publication of industry-supported trials was associated with an increase in journal impact factors. Sales of reprints may provide a substantial income. We suggest that journals disclose financial information in the same way that they require them from their authors, so that readers can assess the potential effect of different types of papers on journals' revenue and impact.",
keywords = "Cohort Studies, Conflict of Interest, Disclosure, Drug Industry, Humans, Income, Journal Impact Factor, Manuscripts, Medical as Topic, Periodicals as Topic, Publishing, Randomized Controlled Trials as Topic, Scientific Misconduct, Evaluation Studies, Journal Article",
author = "Andreas Lundh and Marija Barbateskovic and Asbj{\o}rn Hr{\'o}bjartsson and G{\o}tzsche, {Peter C}",
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Conflicts of interest at medical journals : the influence of industry-supported randomised trials on journal impact factors and revenue - cohort study. / Lundh, Andreas; Barbateskovic, Marija; Hróbjartsson, Asbjørn; Gøtzsche, Peter C.

I: P L o S Medicine, Bind 7, Nr. 10, 26.10.2010, s. e1000354.

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

TY - JOUR

T1 - Conflicts of interest at medical journals

T2 - the influence of industry-supported randomised trials on journal impact factors and revenue - cohort study

AU - Lundh, Andreas

AU - Barbateskovic, Marija

AU - Hróbjartsson, Asbjørn

AU - Gøtzsche, Peter C

PY - 2010/10/26

Y1 - 2010/10/26

N2 - BACKGROUND: transparency in reporting of conflict of interest is an increasingly important aspect of publication in medical journals. Publication of large industry-supported trials may generate many citations and journal income through reprint sales and thereby be a source of conflicts of interest for journals. We investigated industry-supported trials' influence on journal impact factors and revenue.METHODS AND FINDINGS: we sampled six major medical journals (Annals of Internal Medicine, Archives of Internal Medicine, BMJ, JAMA, The Lancet, and New England Journal of Medicine [NEJM]). For each journal, we identified randomised trials published in 1996-1997 and 2005-2006 using PubMed, and categorized the type of financial support. Using Web of Science, we investigated citations of industry-supported trials and the influence on journal impact factors over a ten-year period. We contacted journal editors and retrieved tax information on income from industry sources. The proportion of trials with sole industry support varied between journals, from 7% in BMJ to 32% in NEJM in 2005-2006. Industry-supported trials were more frequently cited than trials with other types of support, and omitting them from the impact factor calculation decreased journal impact factors. The decrease varied considerably between journals, with 1% for BMJ to 15% for NEJM in 2007. For the two journals disclosing data, income from the sales of reprints contributed to 3% and 41% of the total income for BMJ and The Lancet in 2005-2006.CONCLUSIONS: publication of industry-supported trials was associated with an increase in journal impact factors. Sales of reprints may provide a substantial income. We suggest that journals disclose financial information in the same way that they require them from their authors, so that readers can assess the potential effect of different types of papers on journals' revenue and impact.

AB - BACKGROUND: transparency in reporting of conflict of interest is an increasingly important aspect of publication in medical journals. Publication of large industry-supported trials may generate many citations and journal income through reprint sales and thereby be a source of conflicts of interest for journals. We investigated industry-supported trials' influence on journal impact factors and revenue.METHODS AND FINDINGS: we sampled six major medical journals (Annals of Internal Medicine, Archives of Internal Medicine, BMJ, JAMA, The Lancet, and New England Journal of Medicine [NEJM]). For each journal, we identified randomised trials published in 1996-1997 and 2005-2006 using PubMed, and categorized the type of financial support. Using Web of Science, we investigated citations of industry-supported trials and the influence on journal impact factors over a ten-year period. We contacted journal editors and retrieved tax information on income from industry sources. The proportion of trials with sole industry support varied between journals, from 7% in BMJ to 32% in NEJM in 2005-2006. Industry-supported trials were more frequently cited than trials with other types of support, and omitting them from the impact factor calculation decreased journal impact factors. The decrease varied considerably between journals, with 1% for BMJ to 15% for NEJM in 2007. For the two journals disclosing data, income from the sales of reprints contributed to 3% and 41% of the total income for BMJ and The Lancet in 2005-2006.CONCLUSIONS: publication of industry-supported trials was associated with an increase in journal impact factors. Sales of reprints may provide a substantial income. We suggest that journals disclose financial information in the same way that they require them from their authors, so that readers can assess the potential effect of different types of papers on journals' revenue and impact.

KW - Cohort Studies

KW - Conflict of Interest

KW - Disclosure

KW - Drug Industry

KW - Humans

KW - Income

KW - Journal Impact Factor

KW - Manuscripts, Medical as Topic

KW - Periodicals as Topic

KW - Publishing

KW - Randomized Controlled Trials as Topic

KW - Scientific Misconduct

KW - Evaluation Studies

KW - Journal Article

U2 - 10.1371/journal.pmed.1000354

DO - 10.1371/journal.pmed.1000354

M3 - Journal article

VL - 7

SP - e1000354

JO - PLoS Medicine

JF - PLoS Medicine

SN - 1549-1277

IS - 10

ER -