Research and Publication Ethics

Contents

MDPI Statement

Publication Ethics Statement

Ethical Guidelines for Authors

Authorship

Plagiarism, Data Fabrication and Image Manipulation

Research Involving Human Subjects

Research Involving the Use of Animals in Research

Research Involving Cell Lines

Research Involving Plants

Clinical Trials Registration

Dual Use Research of Concern

Sex and Gender in Research

Borders and Territories

Potential Conflicts of Interest

Intellectual Property i.a. Copyright, Patent and Licensing

Citation Policies

MDPI Research Data Policies

Ethical Guidelines for Reviewers and Editors

Comments and Complaints

Updating Published Papers

Contact

MDPI Statement

All submitted manuscripts must conform to MDPI’s policies as described. In all instances, MDPI closely follows the Committee on Publication Ethics (COPE) principles of publication ethics laid out in its core practices documents. Their advice includes support on handling issues such as: conflicts of interest, authorship and contributorship issues and disputes, misconduct allegations and data issues, overlap and plagiarism, and peer review integrity.

MDPI Editorial Boards are independent, and the publisher will not interfere with editorial decision making. Where ethical or legal concerns are present, a decision may be changed; acceptance of a manuscript may be rescinded should an ethical issue or conflict with policies be identified. Manuscripts that do not conform to MDPI ethical policies may be withdrawn from submission by the publisher.

MDPI performs checks on all manuscripts to confirm that they conform with the Publication Ethics Guidelines. Some of the checks described are performed with the support of automatic checks, facilitated by SuSy, while others are performed manually by the Journal Editorial Office teams. Where potential issues are flagged, these are confirmed by a human decision maker. Where a manuscript does not conform to policies or is flagged upon check, in many cases, an Academic Editor is consulted.

Publication Ethics Statement

MDPI is a member of COPE. We fully adhere to its Core Practices and to its Guidelines.

MDPI journals uphold a rigorous peer-review process together with clear ethical policies and standards to support the addition of high-quality scientific studies to the field of scholarly publication. 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.

Submitted manuscripts should conform with MDPI editorial policies and ethical policies as outlined on this webpage and MDPI Instructions for Authors. In addition, submissions should adhere to individual journal guidelines.

Principles:

• Prevention—early detection and flagging of potential ethics issues via automated and manual checks of peer review and manuscript.
• Neutrality—to be fair and objective, making assessments to correct the literature where necessary.
• Transparency—keeping all parties informed when possible and appropriate, and providing the time for them to respond.
• Consistency—ensuring standard processes are followed for the investigation of issues and applicability of policies, and principles and flowcharts of COPE are upheld.

Ethical Guidelines for Authors

Authors submitting to MDPI journals must ensure that their manuscripts are ethically sound and meet industry-recognized standards that are reflected in MDPI policies.

Authors who submit their manuscripts to MDPI journals must:

• Accurately present their research findings and include an objective discussion of the significance of their findings.
• Uphold accurate authorship, by including all and only those who qualify for authorship and clearly stating their contribution.
• Disclose any facts that might be perceived as a possible conflict of interest at submission.
• Present their data and methods with attention to detail. Data and methods used in the research need to be presented in sufficient detail in the manuscript so that other researchers can replicate their work. Raw data must be made publicly available unless there is a compelling reason otherwise (e.g., patient confidentiality).
• Be aware that simultaneous submission of manuscripts to more than one journal is not permitted.
• Original research results must be novel and not previously published, and any translations must abide by our policy on translations.
• Obtain permission to publish from the copyright holder for any previously published content (including quotations, figures or tables).
• Communicate errors and inaccuracies found after publication promptly.

This list is not exhaustive, and authors should be aware of local regulations and accepted norms within academic publishing.

Authorship

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 meet all four criteria:

• 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 reviewing 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.

Those who contributed to the work but do not qualify for authorship should be listed in the acknowledgments. More detailed guidance on authorship is given by ICMJE.

Different disciplines adopt their own criteria, for example, the ICMJE (International Committee of Medical Journal Editors) guidelines are well-known in biomedical fields, the APA (American Psychological Association) guidelines are used in Psychology, the EuChemS (European Chemical Society) guidelines are adopted in Chemistry, whereas in the arts, humanities and social sciences, publications by single authors are more common. However, the minimum recognized requirements for authorship are making a substantial contribution to the research and being accountable for the work undertaken (COPE Discussion document: authorship).

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. We reserve the right to request evidence of authorship, and changes to authorship after acceptance will be made at the discretion of MDPI.

Author Contributions

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.

The corresponding author should act as a point of contact between the editor and the other authors, keep co-authors informed, and involve them in major decisions about the publication.

Joint first authors can be indicated by the inclusion of the statement “X and X contributed equally to this paper” in the manuscript. The roles of the equal authors should also be adequately disclosed in the contributorship statement.

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

If authorship is retained by the consortium or group, the consortium or group should be listed as an author. Individual consortium/group author members listed in the author byline must qualify for authorship according to ICMJE guidelines.

Where work is presented by the author(s) on behalf of a consortium or group, this should be clarified in the author list, for example “Author A on behalf of XXX Consortium/Group”. The consortium/group will not retain authorship and will only appear in the author list.

If provided, the consortium/group members will be listed in a separate section at the end of the article in Acknowledgments, Appendix or Supplementary Materials.

Authorship and the Use of AI or AI-Assisted Technologies

MDPI follows the Committee on Publication Ethics (COPE) position statement when it comes to the use of Artificial Intelligence (AI) and AI-assisted technology in manuscript preparation. Tools such as ChatGPT and other large language models (LLMs) do not meet authorship criteria and thus cannot be listed as authors on manuscripts.

In situations where AI or AI-assisted tools have been used in the preparation of a manuscript, this must be appropriately declared with sufficient details at submission via the cover letter. Furthermore, authors are required to be transparent about the use of these tools and disclose details of how the AI tool was used within the “Materials and Methods” section, in addition to providing the AI tool’s product details within the “Acknowledgments” section.

Authors are fully responsible for the originality, validity, and integrity of the content of their manuscript, including any material contributed by AI or AI-assisted tools, and must ensure, through carefully review, that this content complies with all MDPI’s publication ethics policies. MDPI reserves the right to request further information, and editorial decisions will be made in line with MDPI’s Editorial Process and our Terms and Conditions.

Deceased Authors

If a manuscript is submitted with a deceased author included in the authorship, or if an author passes away during peer review, the corresponding author, or co-authors, should inform the editorial office. If the deceased author was a corresponding author, the authorship group should nominate a co-author for this role. The corresponding author should confirm the contribution of the deceased author and any potential conflicts of interest. Upon publication, a note will be added under the author list.

Changes to Authorship

Authors are expected to carefully consider authorship before manuscript submission. Any change to the author list should be made during the editorial process, before manuscript acceptance. Authorship changes, including any addition, removal, or rearrangement of author names will require the approval of all authors including any to be removed. To request any change in authorship, the journal must receive a completed authorship change form that includes the signatures of all authors, and provides a reason for the change. Any changes to authorship requested after manuscript acceptance will result in a delay in publication. If the manuscript has already been published, requests for a change in authorship will be evaluated and require the publication of a Correction. We reserve the right to request evidence of authorship, and changes to authorship after acceptance will be made at the discretion of MDPI.

Authorship Disputes

MDPI follows the Committee on Publication Ethics (COPE) guidelines when it comes to resolving authorship disputes that may occur either during processing or post-publication. Here, COPE guidelines clearly state that Journals are not in a position to adjudicate on appropriate authorship contributions (https:/publicationethics.org/resources/discussion-documents/authorship) and that disputed authorship is not usually grounds for retraction when “there is no reason to doubt the validity of the findings” (https://publicationethics.org/retraction-guidelines).

In situations where disputes cannot be settled by the effected parties, Journals will reach out to an appropriate Institution or Governing Body for final adjudication. MDPI reserves the right to amend authorship lists in line with Institution or Governing Body recommendations.

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.

All MDPI submissions are checked for plagiarism using the industry standard software iThenticate. If plagiarism is detected during the peer review process, the manuscript may be rejected. If plagiarism is detected after publication, an investigation will take place and action taken in accordance with our policies.

MDPI reserves the right to request original images at a sufficiently high resolution and unprocessed data files upon submission, during the peer review process, and for the purpose of post-publication investigation.

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.

Any concerns raised over undeclared image modifications during manuscript processing or after publication will be investigated, and the authors will be requested to provide original images and unprocessed data. In case these data are unavailable upon request, the Editorial Office will halt the peer review process until the issues are satisfactorily resolved. If irregular image manipulation is identified and confirmed during the peer review process, the publisher may reject the manuscript. In instances where irregular image manipulation is identified and confirmed after publication, we may correct or retract the paper, and the issue may be raised with the authors’ institutions.

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.

MDPI encourages authors to retain unprocessed data and metadata files after publication by archiving their datasets on their laboratory or institutional servers, or in public, community-supported repositories, for at least five years after publication.

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 the local institutional review board (IRB) or other appropriate ethics committee must be obtained before undertaking the research to confirm the study meets national and international guidelines. As a minimum, a statement including the project identification code, date of approval, and name of the ethics committee or institutional review board must be stated in Section ‘Institutional Review Board Statement’ of the article.

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)."

For non-interventional studies (e.g. surveys, questionnaires, social media research), all participants must be fully informed if the anonymity is assured, why the research is being conducted, how their data will be used and if there are any risks associated. As with all research involving humans, ethical approval from an appropriate ethics committee must be obtained prior to conducting the study. If ethical approval is not required, authors must either provide an exemption from the ethics committee or are encouraged to cite the local or national legislation that indicates ethics approval is not required for this type of study. Where a study has been granted exemption, the name of the ethics committee which provided this should be stated in Section ‘Institutional Review Board Statement’ with a full explanation regarding why ethical approval was not required.

A written informed consent for publication must be obtained from participating patients. 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). 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 for publication 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. Editors reserve the right to reject any submission that does not meet these requirements.

You may refer to our sample form and provide an appropriate form after consulting with your affiliated institution. 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.

If the study reports research involving vulnerable groups, an additional check may be performed. The submitted manuscript will be scrutinized by the editorial office and upon request, documentary evidence (blank consent forms and any related discussion documents from the ethics board) must be supplied. Additionally, when studies describe groups by race, ethnicity, gender, disability, disease, etc., explanation regarding why such categorization was needed must be clearly stated in the article.

Research Involving the Use of Animals

The editors will require that the benefits potentially derived from any research causing harm to animals are significant in relation to any cost endured by animals, and that procedures followed are unlikely to cause offense to the majority of readers. Authors should particularly ensure that their research complies with the commonly-accepted '3Rs' [1]:

• Replacement of animals by alternatives wherever possible;
• Reduction in number of animals used; AND
• Refinement of experimental conditions and procedures to minimize the harm to animals.

Authors must include details on housing, husbandry and pain management in their manuscript.

For further guidance authors should refer to the Code of Practice for the Housing and Care of Animals Used in Scientific Procedures [2], American Association for Laboratory Animal Science [3] or European Animal Research Association [4].

If national legislation requires it, studies involving vertebrates or higher invertebrates must only be carried out after obtaining approval from the appropriate ethics committee. As a minimum, 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’. Research procedures must be carried out in accordance with national and institutional regulations. Statements on animal welfare should confirm that the study complied with all relevant legislation. Clinical studies involving animals and interventions outside of routine care require ethics committee oversight as per the American Veterinary Medical Association. If the study involved client-owned animals, informed client consent must be obtained and certified in the manuscript report of the research. Owners must be fully informed if there are any risks associated with the procedures and that the research will be published. If available, a high standard of veterinary care must be provided. Authors are responsible for correctness of the statements provided in the manuscript.

If ethical approval is not required by national laws, authors must provide an exemption from the ethics committee, if one is available. Where a study has been granted exemption, the name of the ethics committee that provided this should be stated in Section ‘Institutional Review Board Statement’ with a full explanation on why the ethical approval was not required.

If no animal ethics committee is available to review applications, authors should be aware that the ethics of their research will be evaluated by reviewers and editors. Authors should provide a statement justifying the work from an ethical perspective, using the same utilitarian framework that is used by ethics committees. Authors may be asked to provide this even if they have received ethical approval.

MDPI endorses the ARRIVE guidelines (arriveguidelines.org/) for reporting experiments using live animals. Authors and reviewers must use the ARRIVE guidelines as a checklist, which can be found at https://arriveguidelines.org/sites/arrive/files/documents/Author%20Checklist%20-%20Full.pdf. Editors reserve the right to ask for the checklist and to reject submissions that do not adhere to these guidelines, to reject submissions based on ethical or animal welfare concerns or if the procedure described does not appear to be justified by the value of the work presented.

1. NSW Department of Primary Industries and Animal Research Review Panel. Three Rs. Available online: https://www.animalethics.org.au/three-rs
2. Home Office. Animals (Scientific Procedures) Act 1986. Code of Practice for the Housing and Care of Animals Bred, Supplied or Used for Scientific Purposes. Available online: https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/388535/CoPanimalsWeb.pdf
3. American Association for Laboratory Animal Science. The Scientific Basis for Regulation of Animal Care and Use. Available online: https://www.aalas.org/about-aalas/position-papers/scientific-basis-for-regulation-of-animal-care-and-use
4. European Animal Research Association. EU regulations on animal research. Available online: https://www.eara.eu/animal-research-law

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. Editors reserve the rights to reject any submission that does not meet these requirements.

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

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 international clinical trials register and cite a reference to the registration in the 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.

CONSORT Statement

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.

Dual Use Research of Concern

MDPI follows the practical framework defined in Guidance for Editors: Research, Audit and Service Evaluations and introduced by the Committee on Publication Ethics (COPE). Research that could pose a significant threat, with broad potential consequences to public health or national security, should be clearly indicated in the manuscript, and potential dual-use research of concern should be explained in the cover letter upon submission. Potential areas of concern include but are not limited to biosecurity, nuclear and chemical threats, and research with a military purpose or application, etc. For these manuscripts to be considered for peer review, the benefits to the general public or public health must outweigh the risks. The authors have a responsibility to comply with relevant national and international laws.

Sex and Gender in Research

We encourage our authors to follow the ‘Sex and Gender Equity in Research – SAGER – guidelines’ and to include sex and gender considerations where relevant. Authors should use the terms sex (biological attribute) and gender (shaped by social and cultural circumstances) carefully in order to avoid confusing both terms. Article titles and/or abstracts should indicate clearly what sex(es) the study applies to. Authors should also describe in the background, whether sex and/or gender differences may be expected; report how sex and/or gender were accounted for in the design of the study; provide disaggregated data by sex and/or gender, where appropriate; and discuss respective results. If a sex and/or gender analysis was not conducted, the rationale should be given in the Discussion. We suggest that our authors consult the full guidelines before submission.

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.

Potential Conflicts 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 interests that may be perceived as inappropriately influencing the representation or interpretation of the reported research results. Examples of potential conflicts of interest include but are not limited to financial interests (such as membership, employment, consultancies, stocks/shares ownership, honoraria, grants or other funding, paid expert testimonies and patent-licensing arrangements) and non-financial interests (such as personal or professional relationships, affiliations, and personal beliefs).

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 funding 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”.

Authors can disclose potential conflicts of interest via the online submission system during the submission process. Declarations regarding conflicts of interest can also be collected via the MDPI disclosure form. The corresponding author must include a summary statement in the manuscript in a separate section “Conflicts of Interest” placed just before the reference list. The statement should reflect all the collected potential conflicts of interest disclosures in the form.

See below for examples of disclosures:

Conflicts of Interest: Author A has received research grants from Company A. Author B has received a speaker honorarium from Company X and owns stocks in Company Y. Author C has been involved as a consultant and expert witness in Company Z. Author D is the inventor of patent X.

If no potential perceived conflicts exist, the authors should state:

Conflicts of Interest: The authors declare no conflicts of interest.

MDPI acknowledges the importance of publishing research regarding smoking cessation or reduction in tobacco use. While we accept submissions on these topics, MDPI does not publish studies funded partially or fully by the tobacco industry. Other privately funded studies—for example, 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.

Intellectual Property i.a. Copyright, Patent 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's 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]”.

Preprints

MDPI accepts submissions that have previously been made available as preprints, provided that they have not undergone peer review, and does not consider preprints of prior publications that would prevent publication after peer review. Authors are required to disclose a preprint posting (DOI and licensing terms) during manuscript submission to an MDPI journal or at any other stage of the review process. Once the submitted manuscript has been published, authors are encouraged to consider updating the preprint record with the publication reference (DOI and link to the publication on the journal website). MDPI’s policy on preprints is informed by COPE guidelines and recommendations, and more details can be accessed via the following link.

• Authors should not update the preprint with any version of the paper while undergoing peer review, as the peer-review process is confidential;
• Authors should disclose any changes in authorship between the preprint version and the version submitted to the journal (the journal can ask for an explanation about any significant changes in authorship);
• Authors should cite any relevant preprints that they have considered during the research for or writing of their paper.

Translations

MDPI journals may consider high-quality content that has been previously published in a different language for publication, provided that the original study is appropriately referenced in the Acknowledgments section.

• Authors should clearly declare that their paper is a translated version in the cover letter at submission;
• All authors from the original publication must appear on the submitted manuscript;
• Appropriate permission must be sought and granted from the publisher, copyright holders, and/or authors of the original article prior to manuscript submission;
• Relevant documentation relating to these permissions must be uploaded in the Supplementary Materials section during submission;
• The journal editor must be informed about the publishing history of the previously published content;
• The original article must be referenced in the Acknowledgments section.

“This is a translation/reprint of (insert title here) originally published in (insert language) by (insert publisher) (insert journal name, year, issue/volume number, page numbers). This translation was prepared by (insert name) with support from (insert name of funding source, if any). Permission was granted by (insert publisher, copyright holder, and/or authors name).”

Any translated articles that do not follow the above guidelines are unacceptable. Those that pass the pre-check will be peer-reviewed in accordance with MDPI’s editorial process.

Patents

MDPI journals provide fast, rigorous peer review and rapid publication following acceptance. Accepted articles are immediately available online, complete with a DOI, and published on an ongoing basis regardless of their issue’s date of release. Publication, peer review and editorial procedures, proofreading and copyediting, and any other processes will not be postponed for pending issues relating to patent applications or intellectual property. Authors are responsible for ensuring that all patent applications and intellectual property issues are resolved prior to publication. Any patent applications or registrations should be declared in accordance with MDPI’s Conflicts of Interest Policy.

Citation Policies

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 including, but not limited to protocols, analytic methods, raw data, processed data, code, software, algorithms, and study material. The data should be FAIR – findable, accessible, interoperable, and reusable – so that other researchers can locate and use the data.

We recommend that data and code should be deposited in a trusted repository that will allow for maximum reuse (see the Data Preservation section below). If this is not possible, authors are encouraged to share the specific reason in the Data Availability Statement and make this material available upon request to interested researchers. In addition, research materials necessary to enable the reproduction of an experiment should be indicated in the Materials and Methods section. 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 clarify the availability status of the data upon submission and make any limitations or exceptions clear in the Data Availability Statement. Authors should ensure that the data shared is in accordance with consent provided by participants on the use of confidential data. Authors should ensure that the publication of such data does not compromise the anonymity of the participants or breach local data protection laws.

In situations where access is restricted to protect confidential or proprietary information, authors will be requested to clearly explain the restrictions on the dataset and make the data available upon request, with permission for the purposes of peer review.

MDPI recognizes that some institutions and funding agencies only require the retention of research data for a finite period after a project’s completion or publication. However, there are no such limits specified within the MDPI Data Availability Policy and, therefore, we encourage the authors to archive their research data through appropriate data repositories or provide us with minimal datasets within Supplementary Material.

Data availability statements

Data availability statements are required for all articles published with MDPI. During the peer-review and editorial decision process, authors can be asked to share existing datasets or raw data that have been analyzed in the manuscript, and whether they will be made available to other researchers following publication. Authors will also be asked for the details of any existing datasets that have been analyzed in the manuscript.

Below are the recommended Data Availability Statements:

Data preservation

MDPI acknowledges that researchers, institutions, journals, and data repositories have a shared responsibility to ensure long-term data preservation, and MDPI encourages authors to select data repositories with this goal in mind.

MDPI encourages authors to commit to preserving their datasets on their laboratory or institutional servers, for at least five years after publication. If, during that time, the repository to which the data were originally submitted disappears or experiences data loss, we may ask the authors to upload the data to another repository and publish a correction or update to the original publication.

If authors remove their data from the original public repository or change access criteria in a manner that is inconsistent with the publication, we may ask authors to notify the editorial office as soon as possible.

How to choose an appropriate data repository

MDPI encourages the submission of data to community-recognized data repositories where possible. We recommend the authors visit re3data.org or fairsharing.org to help identify registered and certified data repositories relevant to their subject area if no community resource is available. If the authors’ institution has its generalist data repository this can be used to host authors’ data as long as the repository can mint DataCite DOIs, and allows for data to be shared under open terms of use (for example the CC0 waiver).

Data repository criteria

The following criteria should be considered when selecting an appropriate repository, ensuring that platforms:

• Ensure long-term persistence and preservation of datasets in their published form;
• Provide stable identifiers for submitted datasets (DOIs in most cases);
• Allow public access to data without barriers, such as logins or paywalls;
• Support open licenses (CC0 and CC-BY, or their equivalents, are required in most cases);
• Provide confidential review of submitted datasets without the requirement for reviewers to provide identifying information.

Data citation

Authors are encouraged to formally cite any datasets stored in external repositories that are mentioned within their manuscript, including the main datasets that are the focus of the submission, as well as any other datasets that have been used in the work. For previously published datasets, authors should cite both the related research articles and the datasets themselves. Appropriate citation of data is checked and enforced by Journal Editorial staff before publication.

Ethical Guidelines for Reviewers and Editors

Along with the Editorial Office, all participants in the peer-review process, including Editors-in-Chief, Editorial Board Members, Guest Editors and Reviewers, take responsibility for overseeing the integrity of MDPI’s editorial process.

If a participant in the peer-review process has ethical concerns about a manuscript sent for review or decision, or receives information about a possible ethical issue after publication, they must contact the Editorial Office as soon as possible. The Editorial Office will then conduct an investigation as per the MDPI Comments and Complaints Policy and in accordance with COPE guidelines.

Before and during peer review, the following checks are performed by Managing Editors and Assistant Editors in the Editorial Office. However, concerns from Reviewers and Editors should still be reported to the Editorial Office.

1. Ethics approval and permissions for research involving human subjects, animals or cell lines.
2. Plagiarism, duplicate publication, and necessary permission from the copyright holder to include already-published figures or images.
3. Clinical Trials Registration, and reference to the registration in the Methods Section.
4. Other compliance, ethics and research integrity checks in accordance with MDPI policies and guidelines.

When making a recommendation or final acceptance decision on a manuscript, Reviewers and Editors should consider:

1. Any facts that might be perceived as a possible conflict of interest must be disclosed, and authors must disclose conflicts of interest relating to their manuscript or study prior to submission.
2. Authors must accurately present their research findings and include an objective discussion of the significance of their findings.
3. Data and methods used in the research need to be presented in sufficient detail in the paper, so that other researchers can replicate their work.
4. Whether or not the submission fits the scope of the journal.
5. Reviewers provided sufficient feedback and were suitable to review the submission.

Potential Conflicts of Interests

We support transparency, and all those involved in the peer-review process must carefully consider and declare any conflicts of interest when participating in the review, decision-making process, and publication of an article. All associations that interfere with, or could be potentially perceived as interfering with, the full and objective assessment, peer review and decision-making process must be declared.

Even if a Reviewer or Editor believes that the existence of a conflict of interest, or several conflicts of interest, will not impact the peer review or decision-making process, the Reviewer or Editor should remove themselves from the process to avoid the perception of a conflict of interest and to protect the integrity of the peer-review process.

Types of Conflicts of Interest

Personal or Collaborative

Neither Reviewers nor Editors should take part in the review of manuscripts submitted by authors who are affiliated with their own institution, by authors who are research or project collaborators, or by any authors who are personal friends, family members, or spouses. Reviewers or Editors should not take part in the review or decision-making process of manuscripts submitted by authors who currently represent or have represented a mentor or mentee role or relationship in the past, or those with whom they have collaborated or coauthored in the last 3 years.

Financial or Professional Conflicts

Financial conflicts include any professional or business relationships, financial or commercial interests, or other competing interests that may be viewed as potentially introducing bias into the review process. Neither Reviewers nor Editors should receive professional or personal benefits, salary, board membership, funding or grants from a company or companies with interests in the reported results or other aspects of the manuscript content, honoraria, or hold any other interests in a company whose product is discussed in the article, or intellectual property rights such as patents, royalties, and copyright as a result of their contribution. Reviewers and Editors should not take part in the review or decision-making process of manuscripts where conflicts of interest that may be viewed as potentially introducing bias are present.

Other Conflicts

Any other conflicts of interest, either real or potentially viewed as influencing the outcome of peer review and the decision-making process, should be declared. Reviewers and Editors should evaluate the manuscript’s merit, originality and appropriateness for the journal in accordance with MDPI editorial guidelines. MDPI aims to build journals that are diverse and inclusive, and discrimination based on race, color, sex, gender identity, sexual orientation, age, religion, country of origin, physical ability, or socio-economic status has no place in MDPI journals. Reviewers and Editors must disclose personal biases that may affect peer review.

In the event of a conflict of interest, alternative Reviewers and/or Editors will be found. If an Editor submits a manuscript to the journal, their submission will be handled by other Editors who do not have a conflict of interest.

Confidentiality and Anonymity

Reviewers and Editors must keep the content of the manuscript, including the abstract, confidential. Reviewers must inform the Editorial Office if they would like a student or colleague to complete the review on their behalf.

MDPI journals perform 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 peer review reports; however, MDPI will not reveal reviewer names until publication and only with their explicit agreement. Further information can be found in Open Peer-Review Option.

Comments and Complaints

Readers who have concerns or complaints about published papers should first contact the corresponding author to attempt a resolution directly, before contacting the Editorial Office.

The Editorial Office may be contacted in cases where it is not appropriate to contact the authors, if the authors were not responsive, or if the concerns were not resolved. The Editorial Office will coordinate with the complainant, author/s and Editors-in-Chief or Editorial Board members for the investigation, remedy or resolution of any concerns or complaints.

Complaints, comments, or update requests relating to scholarly validity, ethical or legal aspects of either the paper or its review process will be investigated further where appropriate. All complaints, comments or update requests relating to published papers are investigated by the Editorial Office with the support of the Editorial Board and final approval by the Editor-in-Chief. For ethical concerns, final decisions are made by the Editor-in-Chief or Editorial Board members who are supported by the Editorial Office to promote adherence to core principles of publication ethics as expressed by the COPE. Other persons and institutions will be consulted as necessary, including university authorities, or experts in the field. Legal counsel may be sought where the complaint has legal implications.

Personal comments or criticisms will not be entertained. All complaints are investigated, including anonymous complaints. Complainants may request that the Editorial Office handle their complaint confidentially and the Editorial Office, any Editors-in-Chief or other Editorial Board members will attempt to do so insofar as is appropriate and in accordance with our internal procedures.

Decisions about Corrections, Comments and Replies, Expressions of Concerns, or Retractions resulting from an investigation are made by Editors-in-Chief, Section Editors-in-Chief or Editorial Board members, and communicated to authors. All updates are required to follow our policy on Updating Published Papers.

If a complaint is not considered to be substantiated, then further communication will only be considered if additional information evidencing concerns is presented.

Complainants might not be updated about the status of an investigation until a final decision has been reached, however complainants will be notified if an update is published. The Editorial Office and Editorial Board members are under no obligation to present further detail. Communication will be ended where it is not considered cordial or respectful. Readers with complaints or concerns should be aware that investigations take time to conduct.

When raising concerns to the Editorial Office, please use the Contact Form or contact details below, and, in addition to details about the paper, please also include details of the complaint, its scholarly, scientific or academic validity, a summary of the main points and any other issues, details of any correspondence already had with the authors and a statement clarifying any actual, potential or perceived conflicts of interest.

Updating Published Papers

MDPI recognizes our responsibility to correct scientifically relevant errors or ethical issues that have been brought to our attention. To offer transparency regarding any changes for our authors and readers, we have the following standardized criteria in place for updates to any of our published papers.

Direct update

Direct updates are updates made directly to the publication and can be completed in certain situations (please refer to our correction reference guide) if deemed by the Editorial Office to be a reasonable request. Once approved, the paper will be updated and re-published on our website. Following this, all relevant indexing databases will be notified to ensure that the database versions have also been revised.

Corrections

MDPI distinguishes between Minor and Major corrections.

• Minor corrections address issues that do not impact the scientific content of an article but require an updated version to be uploaded to the version of the record (VoR). Should this update be approved, it will be accompanied by the addition of a footnote on the pdf version and the addition of a “correction statement” located in the backmatter of the website version. A minor correction will not be accompanied by a separate published correction notice.
• Major corrections aim to address issues and errors that could affect the scientific interpretation of an article. Once approved, the paper will be updated and re-published on our website, along with the publication of a correction. This notice is a separate publication that links to the updated paper but is published in the most current issue of the journal. The correction notifies all readers that a significant change has occurred to the paper and that the revised version is now available on the website.

Following both a Minor and Major correction, all relevant indexing databases will be notified to ensure that the database versions have also been revised. You will find further information on our publication update policy in our correction reference guideline.

Author Name Change Policy
Some authors might wish to change their name following publication. In such cases, MDPI will update and republish the article and re-deliver the updated metadata to the appropriate indexing databases (please note that all updates are dependent upon the policies of the databases). Our teams are aware that name changes can be sensitive and/or private in nature, for a variety of reasons that may include alignment with gender identity, marriage, divorce, or religious conversion. Therefore, to protect author identity, a Correction will not be published and co-authors will not be notified. Authors should contact the journal’s Editorial Office with their name change request.

Retractions
Sometimes a paper needs to be retracted 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.

If a Retraction is published, the original publication is amended with a “RETRACTED” watermark, but will still be 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. Retractions are published using the same authorship and affiliation as the paper being retracted, so that the notice and the original retracted paper can be properly found by readers within indexing databases. The Retraction notice will also be published in the current Issue of the journal. Partial Retractions might be published in cases where results are only partially wrong.

A paper will only be completely removed from MDPI’s website and relevant indexing databases 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.

Comments and Replies
If a reader has concerns about the reported results or methods used in a specific paper, they should approach the journal’s Editorial Office and if deemed reasonable, a Comment may be submitted for potential publication. Comments are short letters to the editors from readers who would like to publicly question a specific paper.

Once a Comment is approved for further peer review, the Editorial Office will then approach the authors of the paper in question and invite them to prepare a Reply to this Comment. The Reply allows the authors to publicly respond to the concerns pointed out by the reader. If the reader’s complaints are substantiated, and the authors are not able to adequately respond to the concerns, a Correction of the original paper may be published, or the paper can be retracted entirely. If authors do not provide a response by the deadline provided, or decide not to respond, the Comment may be published alongside a note that explains the absence of the Reply.

Both Comments and Replies will be reviewed to ensure that:

• the Comment addresses significant aspects of the original paper without becoming essentially a new paper;
• the Reply responds directly to any concerns, without becoming evasive;
• the tone of both publications is appropriate for a scientific journal.

While Comments can criticize the work, they should not criticize the work’s authors. Comments should not reiterate previously published disagreements. No more than one round of Comment and Reply will be facilitated where that discussion is from the same reader/s. MDPI journals only accept the submission of Comments on articles that were published by MDPI.

Further discussion may be recommended to take place in alternative forums, such as at https://sciprofiles.com/discussion-groups/public.