But many journals do not require authors to sign disclosure statements, and there is variability in how COI is defined.
"The failure of some authors to disclose competing interests that conflict with patient care has shaken the confidence of both the general public and health science professionals in peer-reviewed medical literature," the authors write. In an effort to protect the integrity of research and improve the public trust, a number of organizations have published guidelines that include specific recommendations for disclosure of information about authors' COIs as a means for improving transparency. Similarly, journal policies calling for authors to disclose COIs have evolved. "However, it is unclear whether medical journals have consistent policies for defining and soliciting COI disclosures."
Jared A. Blum, M.D., of the Brown University College of Medicine, Providence, R.I., and colleagues examined the COI policies of medical journals in the top 10 percent by impact factor to determine the prevalence and variability of COI disclosure requirements and definitions. The study consisted of a survey and analysis of Instructions for Authors and manuscript submission documents, including authorship responsibility forms for the journals, across 35 subject categories available from March through October 2008, noting language referring to COI disclosure.
The authors found that 228 of 256 sampled journals (89 percent) had language requesting author COI disclosure, and that 54 percent (138) of the sampled journals required authors to submit signed disclosure statements. "This discrepancy between journals having COI policies and requiring signed statements is important, because the corresponding author may be the only author of the manuscript to review a COI policy provided only in the Instructions for Authors. The lack of required signed attestation for each author of a specific manuscript may limit dissemination of the policy to authors of a manuscript beyond the corresponding author, potentially leading to failures of some authors to disclose," they write.
Definitions or examples of possible COIs for submitting authors were provided by 197 journals (77 percent). Of these COI definitions, most included direct financial relationships such as "equities interest or stock ownership" (89 percent) or "consultancies" (84 percent). "A minority included other potential conflicts such as personal relationships (42 percent), paid expert testimony (42 percent), relationships with organizations (26 percent), or travel grants (12 percent)," the authors note.
Dividing journals by subject categories indicated that all internal medicine, respiratory medicine, and toxicology journals studied had comprehensive COI definitions, with 19 of these 24 journals requiring signed disclosure attestations. "In contrast, only 6 of the 19 highest-impact journals in geriatrics and gerontology; radiology, nuclear medicine, and medical imaging; and rehabilitation requested that submitting authors disclose COIs."
The authors add that in comparison to findings of a 1997 study, there appears to have been a substantial increase in the prevalence of COI policies over the past decade.
"These findings are encouraging. However, many journals did not require authors to sign disclosure statements, and there was variability in how COI was defined. With little uniformity among journal requirements, authors may encounter differing, and at times confusing, requests for disclosure or no requests for disclosure. We only assessed the means by which the journals defined and solicited disclosures and did not determine their publication practices. Readers should consider the potential for undisclosed COIs in medical journals that lack explicit disclosure requirements. Future investigations should determine whether all disclosures of authors are published by journals. Furthermore, it is important to assess whether detailed COI policies and mandating signed disclosure statements from all authors increases accurate reporting of author COIs," the authors conclude.