Double publication

Duplicate publication, multiple publication, or redundant publication refers to publishing the same intellectual material more than once, by the author or publisher. It does not refer to the unauthorized republication by someone else, which constitutes plagiarism, copyright violation, or both.

Multiple submission is not plagiarism, but it is considered academic misbehavior. Multiple publication of the same research can skew meta-analyses and review articles.

A formalization of the policy of disallowing duplicate publications was given by Franz J. Ingelfinger, the editor of The New England Journal of Medicine, in 1969. He coined the Ingelfinger rule term banning republications in the journal. Most journals follow this policy today. The BMJ, for example, requires copies of any previous work with more than 10% overlap of a submission to be submitted before approving a work for publication.

With the advancement of the internet, there are now several tools available to aid in the detection of plagiarism and multiple publications within biomedical literature. One tool developed in 2006 by researchers in Dr. Harold Garner's laboratory at University of Texas Southwestern Medical Center at Dallas is Déjà Vu, an open-access database containing several thousand instances of duplicate publication.

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