Conflicts of interest: call for new editorial policies in European national journals

During the past decade, disclosure of conflicts of interest (COIs) has been considered the key to ensure the credibility of the scientific process [1, 2]. Biases in design, analysis, and interpretation of studies may rise when authors or sponsors have entrusted interests. Therefore, COIs should be made clear to the readers to facilitate their own judgement and interpretation of their relevance and potential implications. Authors are responsible for fully disclosing potential COIs. Failure to do so will upset the confidence of the public, health professionals and scientists in the peer-reviewed medical literature [3]. Efforts to improve transparency and protect the integrity of research, including specific recommendations and guidelines to disclose COIs, have been proposed by many organisations [4, 5]. However, ensuring adequate reporting of all sources of financial support is becoming increasingly challenging for editors as a result of the growing complexity of funding mechanisms. Furthermore, journals have different policies about COI disclosure which can cause confusion as the same author may report different information in different journals which, in turn, might jeopardise the confidence of the readers. In addition, publication of large industry-supported trials may generate many citations and journal income through reprint sales and thereby be a source of COIs for journals. To illustrate this, Andres Lundh et al. [6] fromCopenhagen, Denmark, evaluated six major medical journals (Annals of Internal Medicine, Archives of Internal Medicine, BMJ, JAMA, The Lancet, and New England Journal of Medicine [NEJM]) in order to investigate industry-supported trials’ influence on journal impact factors and revenue. 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 weremore 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 (NEJM and JAMA did not respond!). The authors concluded that publication of industry-supported trials was associated with an increase in journal impact factors. It was suggested that journals disclose financial information in the same way that they require it from their authors, so that readers can assess the potential effect of different types of papers on journals’ revenue and impact. According to the International Committee of Medical Journal Editors (ICMJE), COIs exist when an author (or the author’s institution), reviewer, or editor has financial or personal relationships that inappropriately influence (bias) his or her actions. Four main areas can be discerned: 1) authors’ associations with entities that supported the submitted manuscript, 2) associations with commercial entities with potential interest in the general area of the manuscript, 3) financial association of their spouse (!) and children, and 4) finally, non-financial associations potentially relevant to the submitted manuscript. To prevent ambiguity, authors should be explicitly asked to state whether COIs exist or do not exist. Editors should publish this information if they believe that it is important in judging the manuscript. To overcome these problems, the ICMJE proposed the use of a common vehicle to report COIs and, in October E. E. van der Wall Interuniversity Cardiology Institute of the Netherlands – Netherlands Heart Institute, Utrecht, the Netherlands