We contend that definitions of conflicts of interest (COI) in peer review need to be reassessed to reflect modern research practices. This could markedly increase the speed and quality of peer review.
For example, many potential reviewers are disqualified under current rules on co-authorship. However, research papers now have increasing numbers of co-authors and their interaction may be little more than episodic, with no genuine COI in practice. The judgement of an author who, say, contributed a data set to a paper is unlikely to be corrupted when reviewing a new paper from former co-authors.
In our editorial experience, co-authors typically have a sound understanding of each other's work and provide frank and constructive feedback. Using them as reviewers avoids settling for candidates who may be too far removed from the topic or not sufficiently senior in the field.
We suggest that only long-running co-authorship should be counted as a COI in peer review. Other potential COIs should include supervisor–student relationships, shared institutional affiliations and collaborators working on the same project, with an expiry date if appropriate.