In the process of responding to such queries, we realized that many researchers may have some misunderstandings about authorship.

The first misunderstanding could be about the concept of authorship. An 'author' is generally considered to be 'someone who has made substantive intellectual contributions to a published study.' According to the recommendation of the International Committee of Medical Journal Editors, authorship is based on the following four criteria: (1) substantial contributions to the conception or design of the work; or the acquisition, analysis, or interpretation of data for the work; (2) drafting the work or revising it critically for important intellectual content; (3) final approval of the version to be published; and (4) agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.¹⁾ Acquisition of funding, collection of data, or general supervision of the research group alone does not constitute authorship.²⁾ A ghost author is someone who is omitted from an authorship list despite qualifying for authorship, and a guest or gift author is someone who is listed as an author despite not qualifying for authorship. In Korea, such authorship problems may be considered as research misconduct.

The second misunderstanding may be about the ownership of responsibility for identifying who meets these criteria. It is the collective responsibility of the authors, not the journal, to ascertain that all people named as authors meet all the four criteria.¹⁾ Hence, requests for removal of authors or addition of an extra author may be accepted only if all the authors agree to the change (including excluded or included author).³⁾