Open access publishing, article downloads, and citations: randomised controlled trial

BMJ 2008; 337 doi: (Published 31 July 2008) Cite this as: BMJ 2008;337:a568

E-publication bias - an emerging problem in biomedical research: A cross-sectional study of Annals of the Rheumatic Diseases

Over the last decade electronic procedures have gained increasing
importance in biomedical research, facilitating the process of submitting,
reviewing, and subsequently publishing of research results. The concept of
“Open Access” (OA) publishing means that scholarly communication is made
available to everyone free of charge on the Internet(1). In the field of
biomedical research OA publishing is often financed by authors or sponsors
paying a fee to the publisher in order to have articles published with
immediate free online access(2). A few journals operate entirely under
this model, whereas others such as specialist journals published by the
BMJ group use a hybrid model allowing authors to choose between
subscription access and author-paid OA in all journal volumes.

In this cross-sectional report, we wanted to investigate the
association between funding by industry of biomedical research and author-
paid OA publishing of papers in Annals of the Rheumatic Diseases (ARD)
Studies published during a one-year period, Vol.66 no.10 (Oct 2007) to
Vol.67 no.9 (Sept 2008) referred to as “Extended Reports”, were considered
eligible for inclusion. The primary exposure was defined as declaration of
study funding from an industrial source with commercial interests in the
area studied, while other author-industry affiliations was considered as
secondary exposures. The unambiguous dichotomous access status defined as
subscription access (“locked”) or OA (“unlocked”) was registered as the
outcome measure.

The results are presented in table 1 and 2. Out of 216 papers, 71
(33%) declared to have received funding from an industrial sponsor
considered to have commercial interests within the field. A significantly
higher proportion of industry-funded studies were published “unlocked”
(12/71 [17%] industry funding vs. 11/145 [8%] no industry funding, OR=2.48
(1.03 to 5.94); Chi2= 4.35, p=0.037). Furthermore, studies with at least
one author declaring other affiliations with industry showed a
significantly higher frequency of ”unlocked” papers (Chi2= 10.04,
p=0.002). In 41 (19%) studies at least one author was employed by industry
with commercial interests in the field, but only 22 (54%) of these studies
had authors who met the requirement of declaring this potential competing
interest. As expected, a larger proportion of studies funded by industry
were RCTs (12/71 [17%]), compared to papers that received no funding from
industry (5/145 [3%]); two-sided Fisher’s exact test (p=0.002). However,
there was no significant interaction between study design and funding
status in relation to OA.

Our results indicate that author-paid OA publishing in the biomedical
field preferentially increases accessibility to studies funded by
industry. This may potentially favour dissemination of pro-industry
results to researchers as well as to non-researching physicians(5-7). We
suggest the term “e-publication bias” for this emerging type of
publication bias in OA hybrid journals. Our results may very well have
relevance beyond the BMJ journal ARD and the medical field of
Rheumatology. Furthermore, we found that adequate disclosure of employment
by an industrial company was missing in as many as 46% of the cases, which
supports the continuous need for propagating correct declaration of actual
or potential conflicting interests and funding by industry(3,8,9).

No external funding was received for this study.
The salaries of all researchers during the study period were paid by the
main employers (AKJ, RP and LEK: Region Skåne; RC, EMB: The Parker
Institute, which is funded by the Oak Foundation. Employers had no
influence on the study conduct, interpretation and reporting of results or
the decision to submit this article for publication.


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articles have greater citation impact? A critical review of the
literature. J Informetrics 2007;1:239-248.

2. Giglia E. Open access in the biomedical field: a unique
opportunity for researchers (and research itself). Eura Medicophys

3. Bekelman JE, Li Y, Gross GP. Scope and impact of financial
conflicts of interest in biomedical research: a systematic review. JAMA

4. Patsopoulos NA, Ioannidis JPA, Analatos AA. Origin and funding of
the most frequently cited papers in medicine: database analysis. BMJ

5. Korn D. Conflicts of interest in biomedical research. JAMA

6. Angell M. Industry-sponsored clinical research: A broken system.
JAMA 2008;300:1069-71.

7. Choudhry NK, Stelfox HT, Detsky AS. Relationships between authors
of clinical practice guidelines and the pharmaceutical industry. JAMA

8. Gross CP, Gupta AR, Krumholz HM. Disclosure of financial competing
interests in randomised controlled trials: cross sectional review. BMJ

9. Hussain A, Smith R. Declaring financial competing interests:
survey of five general medical journals. BMJ 2001;323:263-4.

Competing interests:
RC: is editor in the Cochrane Collaboration (Cochrane Musculoskeletal Review group [CMSG]).

Competing interests: No competing interests

20 March 2010
Ane Krag Jakobsen
Robin Christensen, Robert Persson, Else M Bartels, and Lars Erik Kristensen
Dep urology, 4000 Roskilde, DK