Study looks at possible publication bias/conflict of interest in medical journals

A study published in the BMJ analyzed “the extent to which funding and study design are associated with high reprint orders.”  The authors explain:

Reprints of published articles are a potential valuable means of disseminating information. Many individuals and organisations may request reprints, including the authors of the articles themselves, other members of the scientific community, study sponsors, and pharmaceutical companies. The pharmaceutical industry is thought to be the largest purchaser of reprints. After gifts and drug samples, reprints are the most common form of promotional material circulated among doctors by pharmaceutical companies.

Because pharmaceutical companies may buy from journals copies of articles they have funded, reprints of published articles have been suggested as a possible source of conflict of interest that could lead to publication bias. Orders can be worth large sums of money and could potentially influence the chance of a paper being accepted, especially with the current organisational framework, under which editors can be responsible for the journal’s content and its finances. Studies sponsored by the pharmaceutical industry are also more likely to be published in higher impact factor journals than are studies without industry funding.

So they wrote to the editors of the Journal of the American Medical Association, Lancet, New England Journal of Medicine, Annals of Internal Medicine, and BMJ to get data on reprint orders.

It is troubling that only the British journals – the Lancet and the BMJ – agreed to provide that data.  None of the US journals shared their data.

Here’s a synopsis of what the researchers found:

• High reprint articles, irrespective of journal, were significantly more likely to be sponsored by the pharmaceutical industry.
•  Some of the reprint orders were substantial, equating to a large amount of income generated. Thus reprint orders could potentially be a source of publication bias, although our study was not designed with this in mind.
• “because reprints provide considerable sources of revenue, we would suggest that data on reprint orders should be made more available generally and that specific data for reprint orders should be included with individual articles.”