Last year we had to reject a review article submitted to us because of conflict of interest. What seemed to us an ad hoc group reviewed the treatments of a particular condition. The referee was initially impressed by the clarity of the review but was perplexed that one particular treatment was given much greater prominence than it deserved. Eventually he realised - from his own knowledge rather than anything stated in the paper - that the group had been brought together and funded by a particular drug company. The company manufactured the treatment that was given extra attention.

Years ago, when our editorials were unsigned, we came to learn that one researcher who regularly wrote for us had substantial financial interests in pharmaceutical companies which might have benefited or otherwise from what was written in the editorials. Conflict of interest may also arise with letters, and many letters that seem to come from individuals who simply have an interest in the subject are in fact prompted by organisations with an interest, financial or otherwise, in the outcome of the correspondence. This is particularly true with tobacco companies. Or conflict of interest may arise with referees. John Maddox, the editor of Nature, has described several examples from his personal experience.1 In one case, …