For the policies on the research and publication ethics not stated in instructions, ‘Good Publication Practice Guidelines for Medical Journals’ (Korean Association of Medical Journal Editors), ‘Guidelines on Good Publication’ (COPE, Committee on publication ethics) and ‘Committee on Publication Ethics’ of ICMJE can be applied.

1. Author and authorship

An author is considered as an individual who has made substantive intellectual contributions to a published study and whose authorship continues to have important academic, social, and financial implications. To be listed as an author one should have contributed substantially to all 4 categories established by the International Committee of Medical Journal Editors (ICMJE): (1) conception and design, or acquisition, or analysis and interpretation of data; (2) drafting the article or revising it critically for important intellectual content; and (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. These criteria are applicable to those journals that distinguish the authors from other contributors. Authors are required to identify their contributions to the work on the Title page.

2. Duplicate publication

Manuscripts that have been already published elsewhere or in this journal should not be published. When a similar article has been already published elsewhere or in this journal, its copy should be submitted to the editorial office with the relevant manuscript. The editorial board of the CEP will decide whether the relevant manuscript is duplicately published and examine whether it can be published in this Journal. The editorial board of CEP strictly prohibits the following malpractices associated with publication. If one of the malpractices is prominently detected in a paper, the paper will be forcefully retracted by the committee.

The followings are:
Fabrication: Behavior dishonestly creating some records, being not in existence.
Falsification: Behaviors selectively modifying some data from a study or distortedly explaining uncertain things resulted from a statistical analysis of the study.
Plagiarism: Behaviors making a fraudulent use of others’ idea, method, results, and sentence etc. without an appropriate permission from them.

CEP will follow the guidelines by the Committee on Publication Ethics (COPE, http://publicationethics.org) for settlement of any misconduct.

3. Conflict of interest

The corresponding author of an article is asked to inform the editor of the author’s potential conflicts of interest that may influence the interpretation of data. A potential conflict of interest should be disclosed in the manuscript even when the authors are confident that their judgments have not been influenced in preparing the manuscript. All authors should disclose their conflicts of interest, i.e., 1) financial relationships (such as employment, consultancies, stock ownership, honoraria, paid expert testimony), 2) personal relationship, 3) academic competition, and 4) intellectual passion. These conflicts of interest must be included as a footnote on the title page. Each author should certify the disclosure of any conflict of interest with his/her signature.

4. Protection of privacy, confidentiality, and written informed consent

The ICMJE has recommended the following statement for the protection of privacy, confidentiality, and written informed consent: The rights of patients should not be infringed without written informed consent. Identifying details should not be published in written descriptions (patient's names, initials, hospital numbers, dates of birth, or other protected healthcare information), photographs, and pedigrees unless it is essential for scientific purposes and the patient (or his/her parents or guardian) provides written informed consent for publication. However, complete patient anonymity is difficult to achieve; therefore, informed con- sent should be obtained in the event that anonymity of the patient is not assured. For example, masking the eye region of patients in photographs is not adequate to ensure anonymity. If identifying characteristics are changed to protect anonymity, authors should provide assurance that alterations do not distort scientific meaning and editors should take note of this. When informed consent has been obtained, it should be indicated in the published article.

5. Protection of human and animal rights

While reporting experiments that involve human subjects, it should be stated that the study was performed according to the Helsinki Declaration (World Medical Association) and approved by the Research Ethics Committee (REC) or the Institutional Review Board (IRB) of the institution where the experiment was performed. The author should also include the IRB or REC institution name and number in the text. In the case of an animal study, a statement should be provided indicating that the experiment process, such as the breeding and the use of laboratory animals, was approved by the REC of the institution where the experiment was performed or that it does not violate the rules of the REC of the institution or the NIH Guide for the Care and Use of Laboratory Animals (Institute of Laboratory Animal Resources, Commission on Life Sciences, National Research Council). The authors should preserve raw experimental study data for at least 1 year after the publication of the paper and should present this data if required by the editorial board.

6. Registration of the clinical research

Any research that includes a clinical trial is recommended to register to a primary national clinical trial registration site such as http://cris.nih.go.kr/cris/index.jsp or other sites accredited by World Health Organization or ICMJE.