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Publisher's note| Volume 97, ISSUE 1, PA17-A22, January 2023

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Instructions for authors

        GASTROINTESTINAL ENDOSCOPY publishes original papers reporting investigations and observations relating to endoscopic procedures used in the study and treatment of digestive diseases. All submissions undergo peer review. Submissions may be accompanied by supplemental materials posted to the electronic version of the journal; such materials also will be subject to peer review. Careful adherence to submission guidelines will avoid unnecessary delays, as incomplete submissions will be returned to the authors before initiation of the peer review process.

        Ethical concerns

        • Prospective authors should refer to the Uniform Requirements for Manuscripts Submitted to Biomedical Journals

          International Committee of Medical Journal Editors. Uniform requirements for manuscripts submitted to biomedical journals. Available at: http://www.icmje.org. Accessed June 11, 2004.

          (http://www.icmje.org) to familiarize themselves with ethical conventions of publication; specifically, the issues of redundant or duplicate publication, authorship criteria, and potential conflicts of interest.
        • The Editor reserves the right to investigate alleged improprieties related to these conventions.
        • When questions of scientific misconduct or dishonesty in research occur, the Editor reserves the right to proceed according to the guidelines of the Office of Research Integrity.

          Office of Research Integrity. Managing allegations of scientific misconduct: a guidance document for editors. Available at: http://ori.dhhs.gov/. Accessed June 12, 2004.

          Authors may be asked to provide the appropriate documentation of compliance, as well as the data on which the manuscript is based.
        • Investigations involving human subjects or animals must have prior approval of the appropriate institutional review board or an equivalent body. If your research involves interacting with living human subjects or with the data from living human subjects and if you intend to make the results of your research public (eg, publish an article in GIE), your research meets the definition of human subjects research and requires IRB review. This includes retrospective chart reviews.
          World Medical Association Declaration of Helsinki
          Recommendations guiding physicians in biomedical research involving human subjects.

          Institute of Laboratory Animal Resources, National Research Council. Guide for the care and use of laboratory animals. Washington, DC: National Academy Press, 1996. Available at: http://www.nap.edu/reading room/books/labrats/. Accessed June 12, 2004.

        • In countries where institutional review is not established practice, a statement must be included in the methods section that the research was carried out in accordance with the Helsinki Declaration.
          World Medical Association Declaration of Helsinki
          Recommendations guiding physicians in biomedical research involving human subjects.
        • GIE runs SimilarityCheck (iThenticate) on every article submitted.

        Registration of human clinical trials

        Gastrointestinal Endoscopy follows the International Committee of Medical Journal Editors (ICMJE)’s Uniform Requirements for Manuscripts Submitted to Biomedical Journals. All clinical trials submitted to GIE should have been registered BEFORE the trial begins through one of the registries approved by the ICMJE, and proof of that registration, including the date registered and the registration number, must be submitted to GIE along with the article. IRB approval information must be included in the manuscript text, including the date of IRB registration. As of January 2015, all clinical trials as defined by the ICMJE must also have been registered before the trial began (not just randomized clinical trials). For further details and a list of ICMJE-acceptable registries, please go to http://www.icmje.org.

        Special subject repositories

        Certain repositories such as PubMed Central (“PMC”) are authorized under special arrangement with Elsevier to process and post certain articles such as those funded by the National Institutes of Health under its Public Access policy (see elsevier.com for more detail on our policy).
        Articles accepted for publication in an Elsevier journal from authors who have indicated that the underlying research reported in their articles was supported by an NIH grant will be sent by Elsevier to PMC for public access posting 12 months after final publication. The version of the article provided by Elsevier will include peer-review comments incorporated by the author into the article. Because the NIH ‘Public Access’ policy is voluntary, authors may elect not to deposit such articles in PMC. If you wish to ‘opt out’ and not deposit to PMC, you may indicate this by sending an e-mail to .
        There will be no need for you to post your manuscript directly to PubMed Central, and any such posting is prohibited. Individual modifications to this general policy may apply to some Elsevier journals and to its society publishing partners.

        Manuscript types

        GASTROINTESTINAL ENDOSCOPY will consider the following types of submissions. Authors should consider these categories and review recent issues of the journal when preparing submissions. If you believe that your article should exceed these word lengths, please contact Senior Managing Editor, Publications, Stephanie Kinnan at [email protected] and explain the reasons. Word count does NOT include the abstract, tables, figure legends, or references.
        • Original Article: work limited to 3500 words reporting basic science or clinical investigations in areas relevant to gastrointestinal endoscopy.
        • Systematic Review and Meta-Analysis (SRMA): limited to 3500 words. Critical appraisal of the current literature on a well-defined research question. Follow the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines for an accurate report of the SRMA (www.prisma-statement.org). GIE also encourages the registration of the protocol of the SRMA at the PROSPERO (International Prospective Register of Systematic Reviews) database (crd.york.ac.uk). Meta-analysis should be avoided when the quality of primary studies is suboptimal.
        • Review Article: extensive review of the published literature, limited to 3500 words, on a particular, well-defined topic. Do not combine with reports of individual cases. If interested, please contact Dr. Shivangi Kothari at [email protected]
        • New Methods and Materials: report of experience with new developments in the endoscopic arena, given in no more than 3500 words and no more than 25 references. The report should contain truly novel information. Articles describing only a minor change to an existing procedure are discouraged.
        • At the Focal Point: unusual or classic findings illustrated by no more than four high-quality images, accompanied by a brief description of no more than 200 words. Please be sure a similar image has not appeared in GIE in the past 10 years.
        • Technical Review: systematic, scholarly overview of technologic advances in endoscopy, authored by a single individual and limited to 3500 words.
        • Perspectives: thoughtful and thought-provoking topical reviews of nonclinical areas pertaining to gastrointestinal endoscopy, usually limited to no more than 3000 words. Please be aware that most of these are by invitation, although the editors are open to suggestions that could be considered in some circumstances. If interested, please contact Dr. Monique Barakat at [email protected]
        • Pathology: clinicopathologic section with reviews coauthored by a pathologist and a gastroenterologist that address timely topics in everybody’s clinical practice, limited to 3500 words. These are by invitation only.
        • Thinking Outside the Box: an opinion piece of no more than 1000 words on a provocative matter or novel unexplored concept related to the practice of endoscopy, possibly accompanied by editorial comment; no abstract necessary.
        • Letter to the Editor: reader comments about previously published GIE articles, limited to 300 words and 10 references. Not to be used for case reports.

        Submission requirements

        • Original submissions will be considered for publication with the understanding that they are contributed solely to Gastrointestinal Endoscopy. If any material related to the submission (other than a brief abstract) has been published in any medium or has been submitted for publication elsewhere, the authors should provide copies of all related manuscripts, and outline the relationship of all materials for the Editor, to avoid allegations of duplicate publication.
        • All manuscripts must be submitted online at http://www.editorialmanager.com/gie/. This website provides step-by-step instructions for manuscript submission as well as a tutorial for authors.
        • All peer review, tracking, and follow-up will be done through this system.
        • Articles must be written in standard English. All accepted manuscripts are subject to copy editing for conciseness, clarity, grammar, spelling, and journal style. Authors who are not native English speakers are strongly encouraged to have their manuscript proofread by a native English-speaking researcher PRIOR TO SUBMISSION. Articles that refer to currency must use U.S. currency.
        • For all instances of the word “complications,” substitute “adverse events.”
        • IRB approval and clinical trial registration are required. Please include this information with your submission. See REGISTRATION OF HUMAN CLINICAL TRIALS (see first page of instructions for authors) for further information.
        • All listed authors must meet ICMJE requirements for authors. See the requirements at http://www.icmje.org/recommendations/browse/roles-and-responsibilities/defining-the-role-of-authors-and-contributors.html.

        Your paper your way

        New Submissions

        Submission to this journal proceeds totally online, and you will be guided stepwise through the creation and uploading of your files. The system automatically converts your files to a single PDF file, which is used in the peer-review process. As part of the Your Paper Your Way service, you may choose to submit your manuscript as a single file to be used in the refereeing process. This can be a PDF file or a Word document, in any format or lay-out that can be used by referees to evaluate your manuscript. It should contain high enough quality figures for reviewing. If you prefer to do so, you may still provide all or some of the source files at the initial submission. Please note that individual figure files larger than 10 MB must be uploaded separately.
        Please note: If your article is selected for revision or acceptance, you will, at that point, have to follow the usual journal requirements for submitting separate files in the appropriate formats.

        References

        There are no strict requirements on reference formatting at submission. References can be in any style or format as long as the style is consistent. Where applicable, first 3 author(s) name(s), journal title/book title, chapter title/article title, year of publication, volume number/book chapter and the pagination must be present. The reference style used by the journal will be applied to the accepted article by Elsevier at the proof stage. Note that missing data will be highlighted at proof stage for the author to correct.

        Formatting requirements

        There are no strict formatting requirements, but all manuscripts must contain the essential elements needed to convey your manuscript, for example Abstract, Keywords, Introduction, Materials and Methods, Results, Conclusions, Artwork and Tables with Captions. If your article includes any Videos and/or other Supplementary material, this should be included in your initial submission for peer-review purposes. Divide the article into clearly defined sections. Please do not format your manuscript in double-column layout.

        Use of wordprocessing software

        Regardless of the file format of the original submission, at revision you must provide us with an editable Word file of the entire article. Keep the layout of the text as simple as possible. Most formatting codes will be removed and replaced on processing the article. The electronic text should be prepared in a way very similar to that of conventional manuscripts (see also the Guide to Publishing with Elsevier: http://www.elsevier.com/guidepublication). See also the section on Electronic artwork. To avoid unnecessary errors, you are strongly advised to use the “spell-check” and “grammar-check” functions of your wordprocessor.

        Figure captions

        Ensure that each illustration has a caption. A caption should comprise a description of the illustration (not on the figure itself). Keep text in the illustrations themselves to a minimum but explain all symbols and abbreviations used.

        Journal publishing agreement

        • At the time an article is accepted and sent to Elsevier for production, a Journal Publishing Agreement will be e-mailed to the corresponding author. This original document, containing the author(s) ink signatures, should be returned to Elsevier at the following address. This must be on file before publication can occur.
        Pushpa Vairam
        Elsevier, Inc.
        230 Park Avenue
        Suite 800
        New York, NY 10169
        Fax: 31-2048-52789
        • The Journal Publishing Agreement must be completed in its entirety.
        • The deletion or addition of authors at any point between submission and publication must be explained to the satisfaction of the Editor. The Editor reserves the right to clarify each author’s role in the work outlined.

        Submission format

        Classifications

        Under Enter Classifications, authors must choose as many classifications as is appropriate for the article. Editors and reviewers will be assigned based on the classifications chosen.

        Key Words

        When prompted by the online submission process, authors should provide no fewer than 3 but no more than 5 key words that reflect the content of the manuscript. For guidance, consult the Medical Subject Headings (MeSH terms), available online at http://www.nlm.nih.gov/mesh/meshhome.html.

        Title/Cover Page

        The online instructions will guide you in creating this item. This page also should specify each author’s contribution to the following criteria for authorship: conception and design; analysis and interpretation of the data; drafting of the article; critical revision of the article for important intellectual content; final approval of the article.

        Conflict of Interest Disclosure

        Each submission must include a full conflict of interest disclosure. A potential conflict of interest exists when an author or the author’s institution has financial or personal relationships that could influence or could be perceived to influence the work. Examples of financial conflicts include employment, consultancies, stock ownership, honoraria, paid expert testimony, patent applications, and research and travel grants within 3 years of beginning the work submitted. If there are no conflicts of interest, authors must state that there are none. These disclosures will appear with the article in print and online. Authors must use the GIE disclosure form, available as a link in the Attach Files part of the submission process.
        Associate Editors and Reviewers will recuse themselves from involvement in processing manuscripts when they identify a conflict of interest.
        For a complete explanation of what does and does not constitute a conflict of interest, please see Gastrointest Endosc 2006;63(7):33A-35A or view the document online at www.giejournal.org or www.asge.org.

        Diversity, Equity, and Inclusion Form

        Each full-length article must include a Diversity form, available as a link in the Attach Files part of the submission process. Once you open the form, you have the option to either check the boxes that apply to your article, sign, and return the form with the understanding that this information will be published with your article if it is accepted by GIE, or you have the option to check the box that says you do not want to participate. This choice will NOT affect the scientific consideration of your paper.

        Title

        The title should be descriptive, but not overly long. Do not include brand names or acronyms in the title, and do not indicate the conclusion of the study in the title. If the article describes an animal study, indicate that in the title.

        Abstract

        For Original Articles and New Methods and Materials, a structured abstract of no more than 250 words should use all of the following headings:
        • Background and Aims
        • Methods
        • Results
        • Conclusions
        Do not include brand names in the abstract; rewrite the abstract to include generic terms only. Submissions to Reviews and At the Focal Point do not require an abstract.

        Text Structure

        Manuscripts should be structured according to the following:
        • Title: What is the main conclusion of the study?
        • Introduction: Why carry out the study?
        • Background: What is already known on the issue?
        • Methods: How was the study done?
        • Results: What were the main findings?
        • Discussion: What do these results add to the current body of knowledge?
        • The paper’s emphasis should be on tables, figures, and/or images. Authors should stress why the results are important and what the study adds to current knowledge.

        CONSORT/STROBE/PRISMA

        Randomized controlled trials must be presented according to the CONSORT guidelines (http://www.consort-statement.org).
        • Moher D.
        • Schulz K.F.
        • Altman D.
        CONSORT Group (Consolidated Standards of Reporting Trials)
        The CONSORT statement: revised recommendations for improving the quality of reports of parallelgroup randomized trials.
        Observational studies must be presented according to the STROBE guidelines (http://www.strobe-statement.org). Meta-analyses must be presented according to the PRISMA guidelines (http://prisma-statement.org/statement.htm). The checklist for the appropriate guideline must be filled out and attached to your Original Article or New Methods submission. Checklists are available as links in the Attach Files part of the submission process.
        The paper's emphasis should be on tables, figures, and/or images. Authors should stress why the results are important and what the study adds to current knowledge.

        Author Contributions

        Each author must have made a contribution toward the production of the article, as recommended by the ICMJE at http://www.icmje.org, authorship criteria.

        Product and Drug Names

        Generic drug names should be used; trade names may be inserted in parentheses after the initial mention of the drug. Product names should be treated similarly, listing the manufacturer’s name, city, and state in parentheses. Do not put product or drug names in the title or the abstract of the article.

        Laboratory Values

        Laboratory values should be presented in SI units. For conversion from non-SI units see http://www.techexpo.com/techdata/techcntr.html. After laboratory values, normal values should be presented in parentheses in the text. A separate Word file listing all abbreviations and acronyms will need to be uploaded during the submission process.

        Abbreviations and Acronyms

        Spell out abbreviations and acronyms the first time the terms appear in the text. You may follow the list of standard abbreviations found in the AMA Manual of Style, 11th edition.

        Iverson CL, Flanagin A, Fontanarosa PB, Glass RM, Giltman P, Lantz JC, et al. American Medical Association manual of style: a guide for authors and editors. 9th ed. Baltimore, MD: Williams Wilkins; 1998. p. 319–28.

        Statistics

        • All studies reporting levels of significance must include the sample size calculation and power used in that calculation. Justification for deviating from calculated sample sizes must be addressed.
        • Statistical techniques that do not appear in the published literature should be presented as an appendix. All but the most standard tests should be referenced.
        • For reporting means, standard deviations, and standard error, the following format should be used: “mean (SD)” and “mean ± SE.” For reporting medians, the values of the interquartile range (IQR) and those of the range should be given.
        • Report levels of significance for all comparisons made, whether significant or not, with P-values or confidence intervals.
        • Papers that overstate the level of significance of findings due to multiple comparisons must be adjusted statistically and the results and discussion presented only with respect to the corrected findings. The problem may be avoided through the use of multivariate methods; however, significance levels may be corrected with post-hoc tests, such as Bonferroni’s method. Multiple comparisons of data from a single data set typically can occur in either of the two following situations: repeated measurements of a single variable are tested over time, or several correlated variables are used in different tests of hypotheses.
        • Interpretation of results of regression analyses requires that units of continuous variables as well as categories of discrete or ordinal variables be specified. Additionally, for logistic regression and Cox regression analyses, the baseline or reference category of discrete or ordinal variables must also be given.

        Figures and Tables

        Figures (including color photographs) are published without charge to authors.
        • Instructions for creating figures can be found below and at http://www.editorialmanager.com/gie/.
        • It is crucial that you create your figures at the correct resolution before uploading them to the Editorial Manager website. For step-by-step instructions (with screenshots of common graphics applications for PC or Mac users) on how to create your figures at the proper resolution, see “Application guidelines” at http://authors.elsevier.com. For best results, please follow these guidelines carefully.
        • Figure images should be provided in EPS or TIF format. Graphics software such as Photoshop and Illustrator (not presentation software such as PowerPoint, CorelDraw, or Harvard Graphics) should be used to create the figures.
        • Illustrations should be saved at the highest resolution setting and sized as close to a column width (3 to 4 inches) as possible.
        • Upload each part of each figure separately in Editorial Manager. Do not label figures with numbers or letters; the compositor will use a standardized font. Do be sure to name the figure file with the correct figure number and letter (e.g., Figure 1A). Do not make the figure legend part of the figure tiff file; figure legends must be placed at the end of the Word text file.
        • Use the colors from our “Figure Color Scheme,” located at http://www.giejournal.org/content/figure_color_scheme, to add color to your figure charts and graphs (not tables).
        • Legends should be typed at the end of the text document and include enough information so that figures can be interpreted without reference to the text. Give staining and magnification for photomicrographs of histologic slides.
        • Tables should be Word documents and should be placed at the end of the text Word document. All tables and figures must be cited in the text in consecutive order. Do not add color to tables; standardized color is added by the compositor.
        • At the discretion of the Editor, images and tables may appear in the print version of the Journal, the electronic version, or both.
        • Random figures will be checked for image manipulation.

        Video/Computer Graphics

        • Videos and computer graphics (ie, slide presentations with or without animation) can be submitted through Editorial Manager. If the file is too large to upload into Editorial Manager, please email the GIE Editorial Office at [email protected] for special uploading instructions. Please indicate the video component on the submission cover page.
        • All videos or graphics submitted must be of the highest quality possible.
        • Submissions of videos that were originally recorded through the S-video or RGB outputs of the endoscope processor are desired.
        • Gastrointestinal Endoscopy may edit any video or computer graphics. Reviewers, following the usual policy with illustrations, may suggest changes in the video or computer graphic.
        • A sound track is highly recommended, but not required.
        • Each video file must be less than 300 MB in size. If the file is larger than 300 MB, you will need to break it up into two or more smaller files.
        • Maximum cumulative length of videos or computer graphics is 8 minutes, and materials may be divided into several smaller clips not to exceed 8 minutes in total. If the video or animation is divided into several clips, each clip should be identified at the beginning of the section (eg, Video Clip 1, Graphic 1) and on the disk. Several videos/graphics may be on the same disk, but if they are separate clips, they must be saved as separate files. When needed, use of simple transitions, eg, fade in/out dissolve, dip to color dissolve, are suggested.
        • Concise legends (typed on a separate page) must accompany each video clip or computer graphic presentation.
        • The following formats for video will be accepted: MPEG-1 or MPEG-2 (.mpg), Quicktime (.mov), or Compuserve GIF (.gif). Please contact the publisher about the use of other formats.
        • A graphic will be used in the text to indicate the location of a video clip or computer graphic component. Videos/computer graphics for accepted manuscripts will not be returned, nor will they be accepted separately from a rejected manuscript.
        • If the article is accepted for publication, the video will be digitized and permanently archived on the Gastrointestinal Endoscopy website (http://www.giejournal.org).

        References

        • References must be cited in the text in consecutive order and identified by superscript numbers.
        • It is the author’s responsibility to check the accuracy of all references by verifying them against the original documents. Citations can be verified by using PubMed’s Citation Matcher (http://www.ncbi.nlm.nih.gov/pubmed/citmatch).
        • Examples of correct forms of reference, in accordance with Uniform Requirements for Manuscripts Submitted to Biomedical Journals,

          International Committee of Medical Journal Editors. Uniform requirements for manuscripts submitted to biomedical journals. Available at: http://www.icmje.org. Accessed June 11, 2004.

          are given in the online submission instructions.
        • Follow Index Medicus for journal title abbreviations (http://www.ncbi.nlm.nih.gov/nlmcatalog/journals).
        • References should follow “Vancouver style.” See the examples at http://www.nlm.nih.gov/bsd/uniform_requirements.html.
        • Manuscripts in preparation, personal communications, and other unpublished information should not be cited in the reference list but may be mentioned in the text in parentheses.
        • Follow Index Medicus for journal title abbreviations (http://www.ncbi.nlm.nih.gov/nlmcatalog/journals).
        • The list of references, in numeric sequence, should be typed at the end of the article. In the submitted version of the manuscript, references should not appear as footnotes or endnotes, and if you have used a program such as EndNote or Reference Manager to create them, the links between the reference numbers and the citations must be removed using the following steps: (1) Using the “Select All” feature (Ctrl-A for PCs. Cmd-A for Macs), highlight the entire text of the file, including the references. (2) Use the keystroke command Ctrl-6 for PCs or Cmd-6 for Macs. (3) Save. This will remove the links (permanently) without disturbing the reference numbers or the citations. It is recommended that you save one copy of your manuscript with the EndNote links in place (for your reference) and one copy of your manuscript without the EndNote links (for submission purposes).

        Permissions

        • If excerpts from other copyrighted works are included, the author(s) must obtain written permission from the copyright owners and credit the source(s) in the article. These permissions must be submitted to the Editorial Office before publication can occur.
        • Preprinted forms for use by authors in these cases can be obtained from Elsevier’s Rights Department, Philadelphia, PA, USA: phone (+1) 215-239-3804, fax (+1) 215-239-3805, e-mail
        • Requests may also be completed online via the Elsevier homepage (http://www.elsevier.com/locate/permissions).

        Virtual microscope

        The journal encourages authors to supplement in-article microscopic images with corresponding high-resolution versions for use with the Virtual Microscope viewer. The Virtual Microscope is a web-based viewer that enables users to view microscopic images at the highest level of detail and provides features such as zoom and pan. This feature for the first time gives authors the opportunity to share true high resolution microscopic images with their readers. More information and examples are available at http://www.elsevier.com/about/content-innovation/virtual-microscope. Authors of this journal will receive an invitation e-mail to create microscope images for use with the Virtual Microscope when their manuscript is first reviewed. If you opt to use the feature, please contact [email protected] for instructions on how to prepare and upload the required high-resolution images.

        Articles in press

        • The Editorial Office and Elsevier may choose to publish an article online before we publish it in the journal. Please contact our production department immediately if you do not want us to make any such prior publication for any reason, including disclosure of a patentable invention.
        • GIE now posts uncorrected, non-formatted articles online within a week of acceptance. These articles can be cited immediately upon posting. The file will be replaced with the corrected, formatted file when it is ready.

        Offprints

        The corresponding author will, at no cost, receive a customized Share Link providing 50 days free access to the final published version of the article. The Share Link can be used for sharing the article via any communication channel, including email and social media. For an extra charge, paper offprints can be ordered via the offprint order form which is sent once the article is accepted for publication. Both corresponding and co-authors may order offprints at any time via Elsevier's WebShop (http://webshop.elsevier.com/). Corresponding authors who have published their article open access do not receive a Share Link as their final published version of the article is available open access on ScienceDirect and can be shared through the article DOI link.

        Proofs

        Galley proofs are e-mailed to the corresponding author and must be returned to the publisher by e-mail within 48 hours to avoid delay in publication.
        John Porter
        Journal Manager
        Elsevier Inc.
        Suite 800
        230 Park Avenue
        New York, NY 10169
        E-mail:
        For any further information please contact the Journal Manager or visit our Support Center.

        Bibliography

        1. International Committee of Medical Journal Editors. Uniform requirements for manuscripts submitted to biomedical journals. Available at: http://www.icmje.org. Accessed June 11, 2004.

        2. Office of Research Integrity. Managing allegations of scientific misconduct: a guidance document for editors. Available at: http://ori.dhhs.gov/. Accessed June 12, 2004.

          • World Medical Association Declaration of Helsinki
          Recommendations guiding physicians in biomedical research involving human subjects.
          JAMA. 1997; 277: 925-926
        3. Institute of Laboratory Animal Resources, National Research Council. Guide for the care and use of laboratory animals. Washington, DC: National Academy Press, 1996. Available at: http://www.nap.edu/reading room/books/labrats/. Accessed June 12, 2004.

          • Moher D.
          • Schulz K.F.
          • Altman D.
          • CONSORT Group (Consolidated Standards of Reporting Trials)
          The CONSORT statement: revised recommendations for improving the quality of reports of parallelgroup randomized trials.
          JAMA. 2001; 285: 1987-1991
        4. Iverson CL, Flanagin A, Fontanarosa PB, Glass RM, Giltman P, Lantz JC, et al. American Medical Association manual of style: a guide for authors and editors. 9th ed. Baltimore, MD: Williams Wilkins; 1998. p. 319–28.