Research and Publication Ethics
Publication Ethics Statement
The editors of MDPI journals enforce a rigorous peer-review process together with strict ethical policies and standards to ensure the addition of high-quality scientific studies to the field of scholarly publication. In cases where we become aware of ethical issues, we are committed to investigating and taking necessary action to maintain the integrity of the literature and ensure the safety of research participants.
Ethical Guidelines for Authors
Authors wishing to publish their papers in MDPI journals must abide to the following:
- Authors should accurately present their research findings and include an objective discussion of the significance of their findings.
- All and only those who qualify for authorship should be included as authors, and their contribution given in the manuscript.
- Any facts that might be perceived as a possible conflict of interest of the author(s) must be disclosed in the paper prior to submission.
- Data and methods used in the research need to be presented in sufficient detail in the paper so that other researchers can replicate the work. Raw data must be made publicly available unless there is a compelling reason otherwise (e.g., patient confidentiality).
- Simultaneous submission of manuscripts to more than one journal is not permitted.
- Original research results must be novel and not previously published, including being previously published in another language.
- For any content previously published (including quotations, figures or tables), any necessary permission to publish must be obtained from the copyright holder.
- Errors and inaccuracies found after publication must be promptly communicated to the Editorial Office.
MDPI follows the International Committee of Medical Journal Editors (ICMJE) guidelines which state that in order to qualify for authorship of a manuscript, authors must satisfy the following:
- Substantial contributions to the conception or design of the work; or the acquisition, analysis, or interpretation of data for the work; AND
- Drafting the work or revising it critically for important intellectual content; AND
- Final approval of the version to be published; AND
- 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.
Any change to the author list during the editorial process or after publication should be approved by all authors, including any who have been removed. The corresponding author should act as a point of contact between the editor and the other authors and should keep coauthors informed and involve them in major decisions about the publication. We reserve the right to request evidence of authorship, and changes to authorship after acceptance will be made at the discretion of MDPI.
Editors of MDPI journals are permitted to submit to journals they edit, however, they will not be involved in the editorial process and are not permitted to make final decisions on their own work or those of close colleagues.
For complete transparency, all submitted manuscripts should include an author contributorship statement that specifies the work of each author. For research articles with several authors, a short paragraph specifying their individual contributions must be provided.
The following statements should be used: Conceptualization, X.X. and Y.Y.; methodology, X.X.; software, X.X.; validation, X.X., Y.Y. and Z.Z.; formal analysis, X.X.; investigation, X.X.; resources, X.X.; data curation, X.X.; writing—original draft preparation, X.X.; writing—review and editing, X.X.; visualization, X.X.; supervision, X.X.; project administration, X.X.; funding acquisition, Y.Y. All authors have read and agreed to the published version of the manuscript.
Please refer to CRediT taxonomy for an explanation of terms. Authorship must be limited to those who have contributed substantially to the work reported.
For review articles, where individual statements are less applicable, a statement should be included that clarifies who was responsible for the ideation, who performed the literature search and/or data analysis, and who drafted and revised the work.
For articles that are principally based a student’s dissertation or thesis, MDPI recommends that the student is listed as principal author.
Consortium/group authorship should be listed in the manuscript with the other author(s).
If authorship is retained by the consortium or group, the consortium or group should be listed as an author.
Where work is presented by the author(s) on behalf of a consortium or group, this should be clarified in the author list, “on behalf of.” The consortium/group will not retain authorship and will only appear in the author list.
Plagiarism, Data Fabrication and Image Manipulation
Plagiarism is not acceptable in MDPI journals. Plagiarism includes copying text, ideas, images, or data from another source, even from your own publications, without giving credit to the original source.
Reuse of text that is copied from another source must be between quotation marks and the original source must be cited. If a study's design or the manuscript's structure or language has been inspired by previous studies, these studies must be explicitly cited.
If plagiarism is detected during the peer review process, the manuscript may be rejected. If plagiarism is detected after publication, we may publish a Correction or retract the paper. MDPI Editors use the industry standard software Ithenticate to check for text duplication.
Image files must not be manipulated or adjusted in any way that could lead to misinterpretation of the information provided by the original image. Irregular manipulation includes 1) introduction, enhancement, moving, or removing features from the original image, 2) grouping of images that should obviously be presented separately (e.g., from different parts of the same gel, or from different gels), or 3) modifying the contrast, brightness or color balance to obscure, eliminate or enhance some information.
If irregular image manipulation is identified and confirmed during the peer review process, we may reject the manuscript. If irregular image manipulation is identified and confirmed after publication, we may correct or retract the paper.
Data presented must be original and not inappropriately selected, manipulated, enhanced, or fabricated. This includes 1) exclusion of data points to enhance significance of conclusions, 2) fabrication of data, 3) selection of results that support a particular conclusion at the expense of contradictory data, 4) deliberate selection of analysis tools or methods to support a particular conclusion (including p-hacking). We strongly recommend preregistration of methods and analysis.
Research Involving Human Subjects
When reporting on research that involves human subjects, human material, human tissues, or human data, authors must declare that the investigations were carried out following the rules of the Declaration of Helsinki of 1975 (https://www.wma.net/what-we-do/medical-ethics/declaration-of-helsinki/), revised in 2013. According to point 23 of this declaration, an approval from an ethics committee should have been obtained before undertaking the research. At a minimum, a statement including the project identification code, date of approval, and name of the ethics committee or institutional review board should be stated in Section ‘Institutional Review Board Statement’ of the article. Data relating to individual participants must be described in detail, but private information identifying participants need not be included unless the identifiable materials are of relevance to the research (for example, photographs of participants’ faces that show a particular symptom). Editors reserve the right to reject any submission that does not meet these requirements.
Example of an ethical statement: "All subjects gave their informed consent for inclusion before they participated in the study. The study was conducted in accordance with the Declaration of Helsinki, and the protocol was approved by the Ethics Committee of XXX (Project identification code)."
A written informed consent for publication must be obtained from participating patients who can be identified (including by the patients themselves). Patients’ initials or other personal identifiers must not appear in any images. For manuscripts that include any case details, personal information, and/or images of patients, authors must obtain signed informed consent from patients (or their relatives/guardians) before submitting to an MDPI journal. Patient details must be anonymized as far as possible, e.g., do not mention specific age, ethnicity, or occupation where they are not relevant to the conclusions. A template permission form is available to download. A blank version of the form used to obtain permission (without the patient names or signature) must be uploaded with your submission.
You may refer to our sample form and provide an appropriate form after consulting with your affiliated institution. Alternatively, you may provide a detailed justification of why informed consent is not necessary. For the purposes of publishing in MDPI journals, a consent, permission, or release form should include unlimited permission for publication in all formats (including print, electronic, and online), in sublicensed and reprinted versions (including translations and derived works), and in other works and products under open access license. To respect patients’ and any other individual’s privacy, please do not send signed forms. The journal reserves the right to ask authors to provide signed forms if necessary.
Ethical Guidelines for the Use of Animals in Research
MDPI journals endorse the ARRIVE guidelines (www.nc3rs.org.uk/ARRIVE) for reporting experiments using live animals. Authors and reviewers can use the ARRIVE guidelines as a checklist, which can be found at www.nc3rs.org.uk/ARRIVEchecklist.
Manuscripts containing original research on animal subjects must have been approved by an ethical review committee. The project identification code, date of approval and name of the ethics committee or institutional review board must be cited in the Methods Section.
For research involving animals, any potentially derived benefits must be significant in relation to harm suffered by participating animals. Authors should particularly ensure that their research complies with the commonly accepted '3Rs':
- Replacement of animals by alternatives wherever possible;
- Reduction in number of animals used;
- Refinement of experimental conditions and procedures to minimize the harm to animals.
Research Involving Cell Lines
Methods sections for submissions reporting on research with cell lines should state the origin of any cell lines. For established cell lines, the provenance should be stated and references must also be given to either a published paper or to a commercial source. If previously unpublished de novo cell lines were used, including those gifted from another laboratory, details of institutional review board or ethics committee approval must be given, and confirmation of written informed consent must be provided if the line is of human origin.
An example of an ethical statement:
The HCT116 cell line was obtained from XXXX. The MLH1+ cell line was provided by XXXXX, Ltd. The DLD-1 cell line was obtained from Dr. XXXX. The DR-GFP and SA-GFP reporter plasmids were obtained from Dr. XXX and the Rad51K133A expression vector was obtained from Dr. XXXX.
Research Involving Plants
Experimental research on plants (either cultivated or wild) including collection of plant material, must comply with institutional, national, or international guidelines. We recommend that authors comply with the Convention on Biological Diversity and the Convention on the Trade in Endangered Species of Wild Fauna and Flora.
For each submitted manuscript supporting genetic information and origin must be provided. For research manuscripts involving rare and non-model plants (other than, e.g., Arabidopsis thaliana, Nicotiana benthamiana, Oriza sativa, or many other typical model plants), voucher specimens must be deposited in an accessible herbarium or museum. Vouchers may be requested for review by future investigators to verify the identity of the material used in the study (especially if taxonomic rearrangements occur in the future). They should include details of the populations sampled on the site of collection (GPS coordinates), date of collection, and document the part(s) used in the study where appropriate. For rare, threatened or endangered species this can be waived but it is necessary for the author to describe this in the cover letter.
Editors reserve the rights to reject any submission that does not meet these requirements.
An example of Ethical Statements:
Torenia fournieri plants were used in this study. White-flowered Crown White (CrW) and violet-flowered Crown Violet (CrV) cultivars selected from ‘Crown Mix’ (XXX Company, City, Country) were kindly provided by Dr. XXX (XXX Institute, City, Country).
Arabidopis mutant lines (SALKxxxx, SAILxxxx,…) were kindly provided by Dr. XXX , institute, city, country).
Clinical Trials Registration
MDPI follows the International Committee of Medical Journal Editors (ICMJE) guidelines which require and recommend registration of clinical trials in a public trials registry at or before the time of first patient enrollment as a condition of consideration for publication.
Purely observational studies do not require registration. A clinical trial not only refers to studies that take place in a hospital or involve pharmaceuticals, but also refer to all studies which involve participant randomization and group classification in the context of the intervention under assessment.
Authors are strongly encouraged to pre-register clinical trials with an international clinical trials register and cite a reference to the registration in the abstract and Methods section. Suitable databases include clinicaltrials.gov, the EU Clinical Trials Register and those listed by the World Health Organisation International Clinical Trials Registry Platform.
Approval to conduct a study from an independent local, regional, or national review body is not equivalent to prospective clinical trial registration. MDPI reserves the right to decline any paper without trial registration for further peer-review. However, if the study protocol has been published before the enrolment, the registration can be waived with correct citation of the published protocol.
MDPI requires a completed CONSORT 2010 checklist and flow diagram as a condition of submission when reporting the results of a randomized trial. Templates for these can be found here or on the CONSORT website (http://www.consort-statement.org) which also describes several CONSORT checklist extensions for different designs and types of data beyond two group parallel trials. At minimum, your article should report the content addressed by each item of the checklist.
Borders and Territories
Potential disputes over borders and territories may have particular relevance for authors in describing their research or in an author or editor correspondence address, and should be respected. Content decisions are an editorial matter and where there is a potential or perceived dispute or complaint, the editorial team will attempt to find a resolution that satisfies parties involved.
MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Copyright and Licensing
For all articles published in MDPI journals, copyright is retained by the authors. Articles are licensed under an open access Creative Commons CC BY 4.0 license, meaning that anyone may download and read the paper for free. In addition, the article may be reused and quoted provided that the original published version is cited. These conditions allow for maximum use and exposure of the work, while ensuring that the authors receive proper credit.
In exceptional circumstances, articles may be licensed differently. If you have specific condition (such as one linked to funding) that does not allow this license, please mention this to the Editorial Office of the journal at submission. Exceptions will be granted at the discretion of the publisher.
For previously published content, it is essential that prior to submission, authors obtain permission to reproduce any published material (figures, tables, text, etc.) that does not fall into the public domain, or for which they do not hold the copyright.
Permission is required for
- Your own work published by other publishers and for which you did not retain copyright.
- Substantial extracts from the work of anyone works or a series of work.
- Use of tables, graphs, charts, schemes and artworks if they are unaltered or slightly modified.
- Photographs for which you do not hold copyright.
Permission is not required for
- Reconstruction of your own table with data already published elsewhere. Please note that in this case, you must cite the source of the data in the form of either "Data from..." or "Adapted from...".
- Very short quotes are considered fair use and therefore do not require permission.
- Graphs, charts, schemes and artwork that is completely redrawn by the authors and significantly changed beyond recognition do not require permission. However, you may need to check the copyright permissions of any underlying data.
Once you have obtained permission, the copyright holder may give you instructions on the form of acknowledgement to be followed. Alternatively, we recommend following the style: “Reproduced with permission from [author], [book/journal title]; published by [publisher], [year]”.
Conflict of Interests
According to The International Committee of Medical Journal Editors, “Authors should avoid entering into agreements with study sponsors, both for-profit and non-profit, that interfere with authors’ access to all of the study’s data or that interfere with their ability to analyze and interpret the data and to prepare and publish manuscripts independently when and where they choose”.
Authors must identify and declare any personal circumstances or interest that may be perceived as inappropriately influencing the representation or interpretation of the reported research results. If there is no conflict of interest, please state, "The authors declare no conflict of interest". Any role of the funding sponsors in the design of the study, in the collection, analyses or interpretation of data, in the writing of the manuscript, or in the decision to publish the results must be declared in this section. If there is no role, please state, “The founding sponsors had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, and in the decision to publish the results”.
MDPI does not publish studies funded by the tobacco industry. Other privately funded studies, especially those associated with the pharmaceutical or food industries, must clearly state the role of the funder. This statement should cover aspects related to how the study topic was selected, experimental design, and collection and analysis of data.
Authors should ensure that where material is taken from other sources (including their own published writing), the source is clearly cited and that where appropriate permission is obtained.
Authors should not engage in excessive self-citation of their own work.
Authors should not copy references from other publications if they have not read the cited work.
Authors should not preferentially cite their own or their friends’, peers’, or institution’s publications.
Authors should not cite advertisements or advertorial material.
In accordance with COPE guidelines, we expect that “original wording taken directly from publications by other researchers should appear in quotation marks with the appropriate citations”. This condition also applies to an author’s own work. COPE have produced a discussion document on citation manipulation with recommendations for best practice.
MDPI Research Data Policies
MDPI is committed to supporting open scientific exchange and enabling our authors to achieve best practices in sharing and archiving research data. We encourage all authors of articles published in MDPI journals to share their research data. Individual journal guidelines can be found at the journal ‘Instructions for Authors’ page. Data sharing policies concern the minimal dataset that supports the central findings of a published study. Generated data should be publicly available and cited in accordance with journal guidelines.
MDPI data policies are informed by TOP Guidelines.
Where ethical, legal or privacy issues are present, data should not be shared. The authors should make any limitations clear in the Data Availability Statement upon submission. Authors should ensure that data shared are in accordance with consent provided by participants on the use of confidential data.
Data Availability Statements provide details regarding where data supporting reported results can be found, including links to publicly archived datasets analyzed or generated during the study.
Below are suggested Data Availability Statements:
- Data available in a publicly accessible repository
The data presented in this study are openly available in [repository name e.g., FigShare] at [doi], reference number [reference number].
- Data available in a publicly accessible repository that does not issue DOIs
Publicly available datasets were analyzed in this study. This data can be found here: [link/accession number].
- Data available on request due to restrictions eg privacy or ethical
The data presented in this study are available on request from the corresponding author. The data are not publicly available due to [insert reason here].
- 3rd Party Data
Restrictions apply to the availability of these data. Data was obtained from [third party] and are available [from the authors/at URL] with the permission of [third party].
- Data sharing not applicable
No new data were created or analyzed in this study. Data sharing is not applicable to this article.
- Data is contained within the article or supplementary material
The data presented in this study are available in [insert article or supplementary material here].
- [dataset] Authors. Year. Dataset title; Data repository or archive; Version (if any); Persistent identifier (e.g., DOI).
Ethical Guidelines for Reviewers
For general guidance on completing a review report, see information for reviewers. The details here cover some specific ethical issues.
Potential Conflict of Interests
We ask reviewers to inform the journal editor if they hold a conflict of interests that may prejudice the review report, either in a positive or negative way. The Editorial Office will check as far as possible before invitation; however, we appreciate the cooperation of reviewers in this matter. Reviewers who are invited to assess a manuscript they previously reviewed for another journal should not consider this as a conflict of interest in itself.
Confidentiality and Anonymity
Reviewers must keep the content of the manuscript, including the abstract, confidential. They must inform the Editorial Office if they would like a student or colleague to complete the review on their behalf.
MDPI journals operate single or double-blind peer review. Reviewers should be careful not to reveal their identity to the authors, either in their comments or in metadata for reports submitted in Microsoft Word or PDF format.
MDPI journals offer authors the possibility to publish review reports with their paper and for reviewers to sign their open review reports but will not reveal reviewer name until publication and only with their explicit agreement.
Ethical Guidelines for Academic Editors
Along with the Editorial Office, Editors-in-Chief, Editorial Board Members, and Guest Editors take responsibility for overseeing the integrity of MDPI’s editorial process. The following provides details on specific ethical aspects of their role.
If the academic editor has ethical concerns about a manuscript sent for review or decision, or receives information about a possible ethical breach after publication, they must contact the Editorial Office as soon as possible. Our Editorial Office will then conduct an investigation according to COPE guidelines.
To support academic editors, checks are made by Managing Editors and Assistant Editors. However, editors should still report any concerns on any aspect. Checks include
- Ethic approval and permissions for research involving human subjects, animals or cell lines.
- Plagiarism, duplicate publication, and that necessary permission from the copyright holder to include already-published figures or images.
- An international clinical trial register for pre-register clinical trials or and to cite a reference to the registration in the Methods Section.
- Author background and qualification.
When making a final acceptance decision on a manuscript, academic editors should consider the following:
- Any facts that might be perceived as a possible conflict of interest of the author(s) must be disclosed in the paper prior to submission.
- Authors must accurately present their research findings and include an objective discussion of the significance of their findings.
- Data and methods used in the research need to be presented in sufficient detail in the paper, so that other researchers can replicate the work.
Updating Published Papers
All MDPI journals have the same policy regarding corrections and retractions. We differentiate between Addendum, Erratum, Corrections, Retractions, Comments, and Expressions of Concern.
Complaints made against papers or requests to update are thoroughly investigated by the Editorial Office with the support of the Editorial Board and final approval by the Editor-in-Chief. Other persons and institutions will be consulted as necessary, including university authorities, or experts in the field.
If crucial results (e.g., missing grant number, additional affiliation, clarify some aspect of methods/analysis, etc) were unintentionally omitted from the original publication, the original article can be amended through an Addendum reporting these previously omitted results. The Addendum will be published, with article numbers added, in the current issue of the journal. A hyperlink to the Addendum will also be added to the original publication, but the original paper does not need to be updated.
An Erratum is a published notification that a formatting change and other non-scientific changes (including changes to authorship) was made to a paper after issue release. The formatting issues may include missing or unclear figures, or text deleted by accident. Very minor errors that do not affect readability or meaning do not need an Erratum published. Thus, we kindly request all the authors to proofread the final version very carefully.
- Before issue release: prior to issue release, corrections on minor issues are directly made to the original, published version of the article on the journal’s website. If the changes may influence the result or conclusions, the academic editors will evaluate the changes. It may be necessary to issue a Correction or Retraction (see below).
- After issue release: Any changes after publication that affect the scientific interpretation (e.g., data in a figure change, conclusions change, whole paragraph added, correct a species name or equation, or add missing details about a method, etc) of a paper made to a paper are announced using a Correction. This is as separate publication that links to the original paper (which is updated). A note will also be added to the Article Versions Notes and to the abstract page, which tells the readers that an updated version was uploaded.
Sometimes an article needs to be completely removed from the body of research literature. This could be due to inadvertent errors made during the research process, gross ethical breaches, fabrication of data, large amounts of plagiarism, or other reasons. Such articles threaten the integrity of scientific records and need to be retracted. MDPI follows the recommendations of the Committee on Publication Ethics (COPE) for retraction. Potential Retractions are thoroughly investigated by the Editorial Office with the support of the Editorial Board and final approval by the Editor-in-Chief. Other persons and institutions will be consulted as necessary, including university authorities, or experts in the field. If a Retraction is published, the original publication is amended with a “RETRACTED” watermark, but will still available on the journal’s website for future reference. However, retracted articles should not be cited and used for further research, as they cannot be relied upon. The Retraction is published, with page numbers added, as a separate item in the current issue of the journal, so that after issue release, the Retraction can be picked up by indexing & abstracting services. Partial Retractions might be published in cases where results are only partially wrong. A paper will only be completely removed in very exceptional circumstances, where leaving it online would constitute an illegal act or be likely to lead to significant harm.
Expression of Concern
For complex, inconclusive, or prolonged situations, an Expression of Concern may be published. If investigations into alleged or suspected research misconduct have not yet been completed or prove to be inconclusive, an editor or journal may wish to publish an Expression of Concern, detailing the points of concern and what actions, if any, are in progress. Very rarely used.
Comments and Replies
Comments are short letters to the editors from readers questioning either the results reported or the experimental methods used in a specific article. Usually, a reader will approach the Editorial Office or the Editor-in-Chief of a journal, if he/she finds an article intriguing. In such circumstances, the Editorial Office may invite the reader to write a short and reasoned Comment on the article. After consideration and review by the Editor in Chief, the Comment may be published, in which case the Editorial Office will approach the authors of the article in question and invite them to prepare a Reply. If the reader’s complaints are substantiated, the authors or the Editorial Office may consequently publish a Correction or retract the paper entirely.
Both comments and replies will be refereed to ensure that
- the comment addresses significant aspects of the original paper without becoming essentially a new paper;
- the reply responds directly to the comment without becoming evasive;
- the tone of both the comment and the reply is appropriate for a scientific journal.
A comment will first be sent to academic editors for an initial check. If it can be proceed, it will be sent to the author of the original paper, who will be given the opportunity to write a reply. Normally, the editor will provide a deadline for receipt of the reply in order to assure prompt publication of the discussion. If a reply is submitted in a timely way, the editor will have both the comment and reply reviewed. If the original author chooses not to submit a reply, the editor may elect to proceed without a reply.
In most cases, editors will invite previous reviewers to review both the Comment and Reply (if have). After receiving review reports, editors will send the Reply and review reports to the author of Comment. The author will be given only one chance to revise the Comment.
The revised Comment and review reports will be sent to the authors of Reply. The authors will also be given only one chance to revise the Reply.
Finally, editors will send the revised Comment/Reply to the academic editor for a final decision.