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Complainant must be made aware that matter cannot be investigated unless at some point the journal Editor informs the corresponding (or complained-about) author (due process) and likely the other journal.

First stage must be a simple comparison of the relevant texts ...

- a simple side-by-side comparison by the Editor for the simpler forms of duplicate publication—a more thoughtful analysis by the Editor if the same research or a single research project is being inappropriately written up as separate articles (see Legal Guidelines)

Note that an identical or similar version of an article may have been published by one journal (often in a national or local edition, usually in a local language) and legitimately republished in another more international journal

The ethical implications of such republication will depend on the editorial policies of the journal - and agreement by the editors of the two journals involved. Republication may be appropriate provided the prior publication and any relevant facts concerning such publication are disclosed to and agreed by the Editor. A brief explanation of these circumstances and full citation details for the previous article should be published along with the newly published version, preferably as a footnote to the title.

If the Editor reasonably determines that the articles are the same or the research reported is substantially the same...

(or should not have been reported in multiple articles), then the Editor should communicate accordingly with the corresponding (or complained-about) author and likely the other journal

Either the Editor or possibly the publishing staff may contact the other journal where the duplicate publication occurred, the Editor more likely to contact the other editor (see Form Letter D for this purpose), Elsevier's publishing staff more likely to contact the publisher

It may be useful for the Editor to involve other peer reviewers, editorial board members, or experts in the relevant field, using standard peer review procedures, to review the texts (especially if the allegation is a more complex form of multiple publication)

In the communication to the corresponding (or complained-about) author (see Form Letter A), Editor may indicate that it is possible that the matter may be referred to institution or company where research took place or any other relevant institution or agency (for example a funding agency) unless the author provides a reasonable explanation (accepted as reasonable by the Editor)