Progress in Preventive Medicine

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Instructions for Authors


Journal Policies

Article Types

Manuscript Preparation and Formatting Instructions

Online Manuscript Submission, Forms, and Licenses

Note: These instructions comply with those formulated by the International Committee of Medical Journal Editors (ICMJE). For further details, authors should consult the following article: International Committee of Medical Journal Editors. “Uniform Requirements for Manuscripts Submitted to Biomedical Journals” New Engl J Med 1997, 336:309–315. The complete document appears at Manuscripts that do not comply with these Instructions cannot be considered for publication and will be sent back to the authors.

The Editorial Office is pleased to answer any questions you may have about preparing your manuscript in accordance with our guidelines. Please contact the editorial office at: [email protected]


Progress in Preventive Medicine (PROGPREVMED) is an open access, peer reviewed journal which aims to publish high quality research that contributes to implementing preventive, personalized, predictive and participatory (P4) medicine. P4 medicine represents a move from models of reacting to illness to maintaining health and a pro-active health care approach; prolonging the healthspan is a primary goal of this new model.

PROGPREVMED is dedicated to highlighting high-quality articles about P4 medicine with a focus on chronic diseases (i.e., lifestyle-related diseases, non-communicable diseases, diseases of civilization) and ageing across the lifespan. The Journal is a cross-discipline research platform to advance the science and clinical practice around implementing P4 medicine to address complex chronic diseases.

PROGPREVMED will publish high-quality original articles, commissioned reviews, commentaries, brief communications, and letters to the Editor. The Journal follows a translational approach ‘From Cell to Community’ – addressing and including all aspects from basic research, to clinical medicine to public health with a focus on systems-based and interdisciplinary approaches.

PROGPREVMED is an official journal of:
- the European Society of Preventive Medicine
- the European Institute for Systems Biology and Medicine
- the Institute for Systems Biology
- the Shanghai Center for Systems Biomedicine
and their associated organizations

As an open access journal, articles are freely available to read online around the world. PROGPREVMED promises to offer a space for researchers to publish and access original research focusing solely on P4 medicine.



The Editors require that each manuscript is an original contribution and that it has not been, and will not be, submitted elsewhere while it is under consideration for publication in PROGPREVMED. Editors may subject any manuscript submitted for consideration of publication in PROGPREVMED to plagiarism-detection software. Manuscripts dealing with material that has appeared or is in press, in brief or preliminary form in other publications will not be considered unless the prior publication is a meeting abstract reporting only summarized information and does not exceed one printed page. The ICMJE has provided details of what is and what is not duplicate or redundant publication. If you are in doubt (particularly in the case of material that you have posted on a web site), we ask you to proceed with your submission but to include a copy of the relevant previously published work or work under consideration by other journals. Authors must draw attention to any published work that concerns the same patients or subjects as the present paper in a covering letter with their article.


The Journal expects that each person listed as an author has participated sufficiently in the intellectual content, the analysis of data, and/or the writing of the manuscript to take public responsibility for it. Each author must have reviewed the manuscript, believes it represents valid work, and approves it for submission. Moreover, should the Editors request the data upon which the manuscript is based, the authors shall produce it. We ask all authors to confirm that they have met the criteria for authorship as established by the ICMJE, believe that the paper represents honest work, and are able to verify the validity of the results reported.

All persons designated as authors should qualify for authorship and all those who qualify should be listed. Each author should have participated sufficiently in the work to take public responsibility for appropriate portions of the content. One or more authors should take responsibility for the integrity of the work as a whole, from inception to published article. Authorship credit should be based only on 1) substantial contributions to conception and design, or acquisition of data, or analysis and interpretation of data for the work; 2) drafting the work or revising it critically for important intellectual content; 3) final approval of the version to be published; and 4) agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. Conditions 1, 2, 3, and 4 must all be met. Acquisition of funding, the collection of data or general supervision of the research group, by themselves, do not justify authorship. All others who contributed to the work who are not authors should be named in the Acknowledgements section.

Any change in authorship/contributions after submission must be approved in writing by all authors and submitted to the Editorial Office for final consideration.

Peer Review Process

All articles published in the Journal are subject to review by the Editor or Co-Editors-in-Chief. Subsequent to an initial review by the Co-Editor-in-Chief and Executive Editors, manuscripts will be forwarded to Senior Editors and sent to at least two independent external peer reviewers. Some letters and invited commentaries may fall outside this review process. Authors submitting manuscripts to the Journal may propose suitable reviewers or oppose reviewers who may have competing interests. Single blind peer review is carried out i.e. the author does not know the identity of the reviewers. Manuscripts are accepted on the basis of quality, originality, significance, novelty and interest to the readers of Progress in Preventive Medicine. A paper that has been formally rejected will not be reconsidered for publication in the Journal.

English Language Assistance

Authors who are not native speakers of English who submit manuscripts to international journals often receive negative comments from referees or editors about the English–language usage in their manuscripts, and these problems can contribute to a decision to reject a paper. To help reduce the possibility of such problems, we encourage such authors to consider using Wolters Kluwer Author Services*.
Wolters Kluwer Author Services

Wolters Kluwer, in partnership with Editage, offers a unique range of editorial services to help you prepare a submission-ready manuscript:

  • Premium Editing: Intensive language and structural editing of academic papers to increase chances of journal acceptance.
  • Advanced Editing: A complete language, grammar, and terminology check to give you a publication-ready manuscript.
  • Translation with Editing: Write your paper in your native language and Wolters Kluwer Author Services will translate it into English, as well as edit it to ensure that it meets international publication standards.
  • Plagiarism Check: Helps ensure that your manuscript contains no instances of unintentional plagiarism.
  • Artwork Preparation: Save precious time and effort by ensuring that your artwork is viewed favorably by the journal without you having to incur the additional cost of purchasing special graphics software.

For more information regarding Wolters Kluwer Author Services, please visit

*Note that the use of such a service is at the author's own expense and risk, and does not guarantee that the article will be accepted.

Abbreviations, Nomenclature and Symbols

Abbreviations, nomenclature and symbols should conform to those found in the AMA Manual of Style. The use of standard international units is encouraged. Abbreviations should be used sparingly and should be spelled out the first time they are used.


All articles dealing with original human or animal data must include a statement on ethics approval at the beginning of the Methods section. This paragraph must contain the following information: the name and address of the ethics committee responsible; the protocol number that was attributed by this ethics committee; and the date of approval by the ethics committee.

The paragraph could read, for example:

Ethical approval for this study (Ethical Committee N° NAC 207) was provided by the Ethical Committee NAC of Geneva University Hospitals, Geneva, Switzerland on 12 February 2015.

In addition, for studies or case reports conducted on human participants you must state clearly in the text that you obtained written informed consent from the study participants; please also look at the latest version of the Declaration of Helsinki. Similarly, for experiments involving animals you must state the care of animal and licensing guidelines under which the study was performed and report these in accordance with the ARRIVE (Animals in Research: Reporting In Vivo Experiments) statement. If ethics clearance was not necessary, or if there was any deviation from these standard ethical requests, please state why it was not required. Please note that the editors may ask you to provide evidence of ethical approval. If you have approval from a National Drug Agency (or similar) please state this and provide details, this can be particularly useful when discussing the use of unlicensed drugs.

Patient’s Privacy

The protection of a patient's right to privacy is essential. Please collect and keep copies of patients’ consent forms on which patients or other subjects of your experiments clearly grant permission for the publication of photographs or other material that might identify them. If the consent form for your research did not specifically include this, please obtain it or remove the identifying material.

A statement to the effect that such consent had been obtained must be included in the ‘Methods’ section of your paper. If necessary the Editors may request a copy of any consent forms.

Data Reporting

PROGPREVMED adheres to the guidelines on adequate data reporting that were established by The Enhancing the QUAlity and Transparency Of health Research (EQUATOR) network (

Financial Support and Competing Interests

A financial disclosure questionnaire must be completed by the corresponding author on behalf of all co-authors at initial submission. The primary purpose of the disclosure section is to determine whether authors have received any commercial financial support that could create a conflict of interest. In addition to monetary interests, a potential for conflict of interest can exist whether or not an individual believes that a relationship (such as dual commitments, competing interests, or competing loyalties) affects his or her scientific judgment. Please review ICMJE Uniform Requirements for Manuscripts Submitted to Biomedical Journals at the following link:

In addition to completing the financial disclosure questionnaire authors must clearly state all relevant conflicts of interest in the Acknowledgements section of the submitted manuscript.


All figures submitted must be owned solely by the author(s). For Figures not meeting this requirement, authors must obtain permission for the use of the figure by Progress in Preventive Medicine. Obtaining this permission is the sole responsibility of the author(s). Credit must be included in the figure legend for all figures being printed with permission.

These requirements apply to the following materials:

  • Previously published materials such as figures and adapted tables or direct quotations of more than 50 words require permission from copyright holder (usually the original publisher).
  • Unpublished data (i.e., from a personal conversation or a manuscript in preparation) require permission from the appropriate investigator.
  • Photographs revealing unmasked faces require permission from the subject(s) of the photograph. If subject- or patient-consent cannot be reached, photographs must be unidentifiable.

Product Information

Medications, materials, and devices must be identified by full non-proprietary name as well as brand name if appropriate and the manufacturer's name. Place this information in parentheses in the text, not in a footnote.


PROGPREVMED is a member of the Committee on Publication Ethics (COPE), and also refers to the ICMJE advice on Scientific Misconduct, Expressions of Concern, and Retraction as well as on Overlapping Publications.


  1. Original Research including basic, clinical and epidemiological research
  2. Reviews
  3. Brief Communications and Correspondence:
    - Editorials
    - Commentaries
    - Viewpoints
    - Letters to the Editors
  4. Open Submission (if the manuscript’s format doesn’t fit any of the article types above).
  5. Invited content:
    - 'State of the Science' series will provide articles by internationally-recognized experts presenting the current understanding and challenges in topical areas that are critical for clinical preventive medicine, P4 Medicine and health. These papers will be by invitation-only.


Manuscripts must be written in clear, grammatical English (see English Language Assistance above). Manuscripts not conforming to Journal format will be returned to authors for modification.

  • Text should be 1.5-spaced.
  • Body text size should be no smaller than 10 pt and no larger than 12 pt.
  • Do not add line numbers as the system will generate those when the PDF is built.
  • Brevity is appreciated. Authors should avoid repeating the same information in the Abstract, Introduction, and Discussion.

Title page, footnotes, abbreviations, and abstract pages must be included in the main body file. Please do not upload separate copies of these documents.

Acceptable document file types for text and tables include .DOC and .DOCX; do not submit a PDF.

Page 1:

Title Page. The following elements are required for every submission:

Title. Include a descriptive title of the work; the title should not be a sentence. No proprietary or brand names for drugs or agents may be used in article titles. Please, include the study design in the title; for instance, “randomised controlled trial”, or “systematic review”. Titles should be as informative and complete as possible.

Authors. Author names should be listed in the following order: the full first name, middle initials, last name of each author, medical and/or highest academic degrees. The name(s) of the department(s) and institution(s) to which the work should be attributed.

When a large group or center has conducted the work, the author list should include the individuals whose contributions meet the authorship criteria defined above, as well as the group name. If the article has been submitted on behalf of a consortium, all author names and affiliations should be listed at the end of the article in the Acknowledgements section.

Address for Correspondence. One author should be designated as the corresponding author. A current email and full mailing address for the corresponding author must be provided.

Page 2:

 Abstract. Original articles should include a structured abstract of no more than 300 words using the following headings: Introduction; Methods; Results; and Conclusions. They should briefly describe, respectively, the problem being addressed in the study, how the study was performed, the salient results, and what the authors conclude from the results. Conventional non-systematic, reviews should include an unstructured abstract of no more than 250 words.

Main Body:

Introduction. The introduction contains a statement of the purpose of the work, the problem that stimulated it, and a brief summary of relevant published investigations.

Methods. Avoid detailed description of previously published methods and cite the appropriate reference. Include appropriate ethical and statistical information.

Results. The results should be concise, avoiding redundant tables and figures illustrating the same data.

Discussion. This section should follow the results and is used to interpret results, with minimal recapitulation of findings.

Acknowledgments: The acknowledgements section should be headed 'Acknowledgements' and contain the following distinct statements in separate paragraphs:

  • Assistance with the study. Acknowledgements should be made only to those who have made a substantial contribution to the study. Authors are responsible for obtaining written permission from people acknowledged by name in case readers infer their endorsement of data and conclusions. If there was no assistance state: ‘Assistance with the study: none.’
  • Financial support and sponsorship. You must make reference to all relevant sources of funding concerning this article. If there were no sources of funding please state: ‘Financial support and sponsorship: none.’
  • Conflicts of interest. You must make reference to all relevant conflicts of interest concerning this article including financial, consultant, institutional and other relationships that might lead to bias or a conflict of interest. If there are no conflicts of interest please state: ‘Conflicts of interest: none.’
  • Presentation (for original articles only). Presentations of preliminary data at, for example, international meetings should be acknowledged separately. If preliminary data was not previously presented please state: Presentation: none.

References: The style of references should conform to the guidelines set forth by the AMA Manual of Style. For specific examples and information regarding references, see the manual or visit online: EndNote users can access a direct download of the JAMA style at Authors using other forms of reference management software should use JAMA style.

  • All references cited in the text must be both listed and cited by the reference number (footnotes are not accepted).
  • Each reference should be cited in the text, tables, or figures in consecutive numerical order by means of superscript Arabic numerals. Use superscript numerals outside periods and commas, inside colons and semicolons. When more than 2 references are cited at a given place in the manuscript, use hyphens to join the first and last numbers of a closed series; use commas without space to separate other parts of a multiple citation (e.g., As reported previously,1,3-8,19...The derived data were as follows3,4,12:)
  • References should be numbered consecutively in the order in which they are cited in the text.
  • References in tables and in figure legends must appear in the reference page(s).
  • In listed references, use the author’s surname followed by initials without periods. (e.g., Doe JF)
  • For references with 6 or fewer authors, list all authors. For references with more than 6 authors, list the first 3 authors followed by “et al.”
    o 1 author Doe JF.
    o 2 authors Doe JF, Roe JP III.
    o 6 authors Doe JF, Roe JP III, Coe RT Jr, Loe JT Sr, Poe EA, van Voe AE.
    o >6 authors Doe JF, Roe JP III, Coe RT Jr, et al.
  • Full-page ranges should be given in expanded form (eg, 426–429, not 426–9).
  • If non-English-language titles are translated into English, bracketed indication of the original language should follow the title.
  • Abbreviate and italicize names of journals according to the style in PubMed; refer to the National Library of Medicine (NLM) Journals Database ( if needed.
  • In references to journals that have no volume or issue numbers, use the issue date, as shown in example 1 below. If there is an issue number but no volume number, use the style shown in example 2. Conversely, if there is a volume number but no issue number, follow example 3.
     1. Author(s). Article Title. Journal Name. Month Year:inclusive pages.
     2. Author(s). Article Title. Journal Name. Year;(Issue No.):inclusive pages.
     3. Author(s). Article Title. Journal Name. Year;vol:inclusive pages.
  •  Papers "submitted for publication" but not yet accepted and citations such as "personal communication" or "unpublished data" are not acceptable as listed references and instead should be included parenthetically in the text. This material, with its date, should be noted in the text as “unpublished data” as follows: (J. F. Doe, MD, unpublished data, January 2010).
  • Papers denoted "in press" (accepted for publication) should appear in the references.
  • Authors are responsible for the accuracy and completeness of the references

Tables: References to tables should be made in order of appearance in the text and should be in Arabic numerals in parentheses, e.g. (Table 1). Each table should be typed on a separate word processing document in 1.5 spacing and uploaded individually. Tables should not be submitted as photographs. Do not embed tables within the manuscript file. Tables are text-only. Do not embed images within the table file. Each table should have a brief title as a heading, appropriate column heads, and any legends. Vertical rules should not be used. Place explanatory matter in footnote, not in the heading. Abbreviations are not permitted in table titles. Any abbreviation(s) used in the body of the table, including dashes, must be defined in the footnotes, listed in reading order. Be sure that each table is cited in the text. If you use data from another published or unpublished source, obtain permission and acknowledge the source fully, using the name of the first author of the previous series, and include the reference number and year along-side the author’s name. Each series mentioned in a table must be listed in the Reference section.

Authors are encouraged to submit non-essential tables as supplemental digital content for publication online only. See Supplemental Digital Content section for more details.

For further information on table formatting, please see the AMA Manual of Style.

Figures and Legends: Figures should be uploaded in the highest resolution available. Legends should be supplied for all figures. They are numbered to correspond with the figures and typed double-spaced on a separate page. Figure legends for any supplemental figures being submitted are to be provided separately; see section, Supplemental Digital Content (SDC).

  • Do not embed figures into the main body file
  • Each figure must be uploaded as a separate file. Each file should be saved as the appropriate figure number (e.g., Figure 1.tif). Label figures using the Description field provided in the Attach Files section of Editorial Manager (e.g. Figure 1, Figure 2). This provides a label for each figure in the PDF generated by Editorial Manager. Do not include the author name in the figure file name.
  • Cite figures consecutively in the manuscript and number them in the order in which they are discussed.
  • All final digital figures for accepted manuscripts must be submitted in EPS, TIFF, or MS Office (DOC, PPT, XLS).
  • Art should be created and scaled to the size intended for publication. Image orientation should be the same as intended for publication.
  • Artwork generated from office suite programs such as CorelDRAW, MS Word, MS PowerPoint and artwork downloaded from the Internet (low resolution JPEG or GIF files) cannot be used.
  • All figures must be designated GRAYSCALE (black and white) or RBG (color).
  • Diagrams, drawings, graphs and other line art (purely black and white figures with no shades of gray) should be prepared at a resolution of 1200 DPI.
  • Halftones images (black/white or color) should be prepared at a resolution of at least 300 DPI.
  • Combination halftones (images containing both pictures and text labeling) should be prepared at 600 DPI.
  • Digital art files should be cropped to remove non-printing borders (such as unnecessary white or black space around an image) and should not include embedded “legend” text, figure titles, or figure numbers.
  • Composite figures may be either submitted as one single print-quality image that is neatly labelled with uppercase letters using Arial/Helvetica bold font or submitted as separate panels (without labels), et, Figure 1A.tif, Figure 1B.tif, to be combined during production if accepted for publication.
  • Legends for all figures should be brief and specific, and should appear on a separate page at the end of the manuscript document, following the list of references. Legends should indicate the figure number and must be numbered correctly.
  • All symbols or abbreviations appearing in an illustration must be defined in the legend; arrows appearing in a figure should be mentioned in the legend.
  • Legends of composite figures should be formatted as a single legend containing necessary information about each part/panel.
  • Your manuscript may be returned to you for correction if the images are of insufficient quality.
  • If photographs of people are used, their identities must be obscured or their written consent to use the photograph must have been obtained. If necessary the Editors may request copies of any consent forms.
  • If a figure has been published before, the original source must be acknowledged and written permission from the copyright holder for both print and electronic formats should be submitted with the material. Permission is required regardless of authorship or publisher, except for documents in the public domain.
  • Figures may be reduced, cropped or deleted at the discretion of the editor.
  • Carefully review the PDF conversion of your submission files to ensure that the figures uploaded without error and appear as intended.

Artwork submitted to the Journal will be checked for quality. Authors submitting a revised paper will have the opportunity to check the quality of their images and make the necessary changes. This step is required for all revisions.

Supplemental Digital Content (SDC): Authors may submit Supplemental Digital Content to supplement the information provided in the manuscript. SDC may include the following types of content: text, tables, figures, references peripheral to information provided as SDC, audio, and video. SDC should be consecutively cited in the Main Body text of the submitted manuscript. SDC files will be available via URL(s) placed at the citation points within the article and are not copyedited by the publisher. They will be presented digitally as submitted. Note that Journal policies for manuscript submission relating to peer review, patient anonymity, ethics, financial disclosure, copyright, and permissions also apply to SDC. Authors should mask patients' eyes and remove patients' names from supplemental digital content unless they obtain written consent from the patients and submit them as supplemental files at the time of the manuscript submission.

Format, File Type and Size Requirements: SDC may be presented in any format (PDF is preferred), and should indicate the article title and first author for clarity. Supplemental content should include a sequential number if submitting more than one (1, 2, 3, etc.). Each SDC in the file should have a visual header in the following name format (e.g., ''SDC, Figure 1''; ''SDC, Materials and Methods'') and a corresponding citation must appear consecutively in the Main Body text. Note that SDC is numbered separately from non-SDC material. If providing SDC figure(s), a figure legend should be included on the figure itself. When uploading SDC select ''Supplemental Digital Content'' as the file designation. For audio and video files, also include the author name, videographer, participants, length (minutes), and size (MB). Video files should be formatted with a 320x240 pixel minimum screen size. Supplemental videos should be submitted using .wmv, .mov, .flv, .qt, .mpg, .mpeg, .mp4 formats only. Videos should not exceed 10 minutes of runtime. Videos must include embedded audio narration in English. For each submission, the SDC file cannot exceed a total size of 10 MB.

For more information, please review Wolters Kluwer’s requirements for submitting Supplemental Digital Content:


New Submissions

Once the manuscript has been created, visit the submission site at to upload the manuscript. Once the manuscript has been vetted for compliance to the Journal's requirements, a manuscript number will be assigned to the submission. Failure to adhere to these guidelines will result in your manuscript being returned to you for correction. Faxed, scanned or emailed copies of manuscripts will not be accepted.

Mandatory License to Publish Forms

Upon first revision, authors will be required to complete a License to Publish (LTP) form. Authors can also provide these at the original submission stage. LTP forms may be signed by the Corresponding Author on behalf of all authors. Authors retain copyright for all articles. Authors grant the journal a license to publish the article and identify itself as the original publisher. Manuscripts will not pass to production without completed forms. LTP forms are available from the submission site homepage

Article Processing Charges
PROGPREVMED is an open access, peer reviewed journal. Authors of accepted peer-reviewed articles pay an article processing charge (APC) to allow perpetual unrestricted online access to their published article to readers globally, immediately upon publication.

The APCs for PROGPREVMED are $1,500 USD for Tier 1 manuscripts (original articles, reviews, guidelines and consensus statements) and $750 USD for Tier 2 manuscripts (commentaries, case reports, editorials and letters to the editor). The APC is charged on acceptance of the article and should be paid within 30 days by credit card by the author, funding agency or institution. Payment must be received in full for the article to be published.

Creative Commons’ license
Open access articles will be freely available to read, download and share from the time of publication. Progress in Preventive Medicine provides authors the choice of applying any of the Creative Commons 4.0 licenses defined below, to be determined after acceptance.

Attribution-NonCommercial-NoDerivs: CC BY-NC-ND

This license is the most restrictive of the six main licenses, only allowing others to download your works and share it with others as long as they credit you, but they can’t change the work in any way or use it commercially.

Attribution-NonCommerical-ShareAlike: CC BY-NC-SA

This license lets others remix, tweak, and build upon your work noncommercially, as long as they credit you and license their new creations under the identical terms.

Attribution-NonCommercial: CC BY-NC

This license lets others remix, tweak, and build upon your work noncommercially, and although their new works must also acknowledge you and be noncommercial, they don’t have to license their derivative works on the same terms.

Attribution-NoDerivs: CC BY-ND

This license allows for redistribution, commercial and noncommercial, of your work as long as it is passed along unchanged and in whole, with credit to you.

Attribution-ShareAlike: CC BY-SA

This license lets others remix, tweak, and build upon your work even for commercial purposes, as long as they credit you and license their new creations under the identical terms. All new works based on yours will carry the same license, so any derivatives will also allow commercial use.

Attribution: CC-BY
This license lets others distribute, remix, tweak, and build upon your work, even commercially, as long as they credit you for the original creation. This is the most accommodating of licenses offered.

Compliance with NIH and other research funding agency accessibility requirements

A number of research funding agencies now require or request authors to submit the post-print (the article after peer review and acceptance but not the final published article) to a repository that is accessible online by all without charge. As a service to our authors, Wolters Kluwer identifies to the National Library of Medicine (NLM) articles that require deposit and transmits the post-print of an article based on research funded in whole or in part by the National Institutes of Health, Howard Hughes Medical Institute, or other funding agencies to PubMed Central. The License to Publish provides the mechanism. Wolters Kluwer ensures that authors can fully comply with the public access requirements of major funding bodies worldwide.

Electronic page proofs and corrections

Corresponding authors will receive electronic page proofs to check the copyedited and typeset article before publication. Portable document format (PDF) files of the typeset pages and support documents (e.g., reprint order form) will be sent to the corresponding author via e-mail. Complete instructions will be provided with the e-mail for downloading and marking the electronic page proofs. Corresponding author must provide an email address. The proof/correction process is done electronically.

​​ It is the author's responsibility to ensure that there are no errors in the proofs. Authors who are not native English speakers are strongly encouraged to have their manuscript carefully edited by a native English-speaking colleague. Changes that have been made to conform to journal style will stand if they do not alter the authors' meaning. Only the most critical changes to the accuracy of the content will be made. Changes that are stylistic or are a reworking of previously accepted material will be disallowed. The publisher reserves the right to deny any changes that do not affect the accuracy of the content. Authors may be charged for alterations to the proofs beyond those required to correct errors or to answer queries. Electronic proofs must be checked carefully and corrections returned within 24 to 48 hours of receipt, as requested in the cover letter accompanying the page proofs.