These are usually requested by the authors of the publication and are represented by a formal online notice in the journal because they affect the publication record and/or the scientific accuracy of published information. Where these amendments concern peer-reviewed material, they fall into one of four categories: erratum, corrigendum, retraction or addendum, described here.

Erratum

Notification of an important error made by the journal that affects the publication record or the scientific integrity of the paper, or the reputation of the authors, or of the journal

Corrigendum

Notification of an important error made by the author(s) that affects the publication record or the scientific integrity of the paper, or the reputation of the authors or the journal. All authors must sign the corrigenda submitted for publication. In cases where Co-Authors disagree, the editors will take advice from independent peer-reviewers and impose the appropriate amendment,  noting the dissenting author(s) in the text of the published version.

Retraction

Notification of invalid results. All co-authors must sign a retraction specifying the error and stating briefly how the conclusions are affected, and submit it for publication. In cases where Co-Authors disagree, the editors will seek advice from independent peer- reviewers and impose the type of amendment that seems most appropriate, noting the dissenting author(s) in the text of the published version.

Retractions are judged according to whether the main conclusion of the paper no longer holds or is seriously undermined as a result of subsequent information coming to light of which the authors were not aware of at the time of publication. In the case of experimental papers, this can include further experiments by the authors or by others that do not confirm the main experimental conclusion of the original publication.

Readers wishing to draw the editors’ attention to published work requiring retraction should first contact the authors of the original paper and then write to the journal, including copies of the correspondence with the authors (whether or not the correspondence has been answered). The editors will seek advice from reviewers if they judge that the information is likely to draw into question the main conclusions of the published paper.

Addendum

Notification of a peer-reviewed addition of information to a paper, usually in response to readers’ request for clarification. Addenda are published only rarely and only when the editors decide that the addendum is crucial to the reader’s understanding of a significant part of the published contribution.