A published article is not changed silently. Any important change is made through a public notice that is linked to the original article, so readers can always see what changed and why. Corrections aim to keep the scholarly record accurate, not to punish authors.

A correction is made when an article contains an error that affects how it should be read, but the main findings are still valid.

Small mistakes such as spelling or formatting are normally not corrected through a notice. The notice is published, linked to the article, and the original article stays online with a note pointing to it.

When there is a serious concern about an article but the evidence is not yet clear, or an investigation is still going on, the editors may publish an expression of concern linked to the article. It is followed later by a correction, a retraction, or a statement that the concern is resolved.

A published article may be retracted when its findings are unreliable or the publication is seriously unethical. Reasons include:

• Major errors that make the results or conclusions invalid.
• Fabrication or falsification of data.
• Plagiarism or duplicate publication (see the Plagiarism Policy).
• Research without ethical approval, or use of data without permission.
• Manipulation of the peer review process.
• Serious undisclosed conflicts of interest.

A retraction can be requested by the authors or started by the editors. The editors make the final decision. The article stays online and is clearly marked as retracted, with a public notice that explains the reason and who requested it.

Before publication, authors may withdraw a submitted manuscript by writing to the editorial office with the title and reasons. Withdrawal is not possible after the manuscript is published; in that case, a correction or retraction is used.

Withdrawing a manuscript that is already in the review or editing process may involve a fee. See Publication Fee for the withdrawal policy. Submitting the same manuscript to another journal while it is under review at JPK is not allowed.

In rare cases, such as defamation, a legal problem, a court order, or a serious risk to safety, the full text of an article may be removed. The title, authors, and a short notice stay online to explain the removal.

1. Email the editorial office with the article title and DOI, what the problem is, and the proposed correction or reason for retraction. For a request from authors, all authors must agree.
2. The editors review the request and decide which action is needed.
3. The authors are informed and may respond before a decision is made.
4. The notice is published and linked to the article.

See also Publication Ethics, Research Misconduct, and Post-Publication Discussion.