CINXE.COM
PLOS Medicine
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name="loc-peer-review"><a href="#loc-peer-review"> Peer Review </a></li> <li data-anchor="loc-editorial-decisions" name="loc-editorial-decisions"><a href="#loc-editorial-decisions"> Editorial Decisions </a></li> <li data-anchor="loc-revisions" name="loc-revisions"><a href="#loc-revisions"> Revisions </a></li> <li data-anchor="loc-accepted-manuscripts" name="loc-accepted-manuscripts"><a href="#loc-accepted-manuscripts"> Accepted Manuscripts </a></li> <li data-anchor="loc-peer-review-history" name="loc-peer-review-history"><a href="#loc-peer-review-history"> Peer Review History </a></li> <li data-anchor="loc-transferring-to-other-journals" name="loc-transferring-to-other-journals"><a href="#loc-transferring-to-other-journals"> Transferring to Other Journals </a></li> <li data-anchor="loc-appeals" name="loc-appeals"><a href="#loc-appeals"> Appeals </a></li> <li data-anchor="loc-contact" name="loc-contact"><a href="#loc-contact"> Contact </a></li> </ul> </nav> <article> <h1>Editorial and Peer Review Process</h1> <div data-section-id="1880"> <p><em><i>PLOS Medicine</i></em> considers research articles and commentary relevant to clinicians, policymakers, and researchers across a range of settings that address the major biological, environmental, social, and political determinants of health. The editors make submission decisions based upon their potential to directly and substantially inform clinical practice or health policy, and their relevance to our international audience.</p> <p>All authors, editors, and reviewers are expected to reply to journal queries in a timely manner, and to comply with <a href="https://plos.org/resources/editor-center/conduct/">PLOS’ Code of Conduct for Editorial Board Members</a> and our policies on <a data-parent-id="15" href="/plosmedicine/s/ethical-publishing-practice#loc-ethical-peer-review">Ethical Peer Review</a> and <a data-parent-id="15" href="/plosmedicine/s/ethical-publishing-practice#loc-standards-for-professional-conduct">Standards for Professional Conduct</a>. Any concerns about the content of correspondence or reviews should be raised to the attention of journal staff by emailing <a href="mailto:plosmedicine@plos.org">plosmedicine@plos.org</a>.</p> </div> <div data-section-id="2332"> <table class="table-basic" style="border:solid 2px #d7df23"> <tbody> <tr> <td style="vertical-align: top"> <div style="width:70px"> <img alt="" class="img-default" src="/plosmedicine/indirect/f119324e643e7f380659d4020c332a2e2e5e2461dea80346c01a96c91ddb5057"> </div></td> <td><strong>Checking the status of your manuscript</strong><br> The corresponding author can check the status of a submitted manuscript at anytime in our <a href="https://www.editorialmanager.com/pmedicine">submission system</a>.</td> </tr> </tbody> </table> </div> <div data-section-id="2438"> <h2><a id="loc-initial-submission" name="loc-initial-submission" data-anchor-id="8054"></a>Initial Submission</h2> </div> <div data-section-id="682"> <table class="table-basic"> <tbody> <tr> <td style="vertical-align: top"> <div style="width: 70px"> <img alt="" class="img-default" src="/plosmedicine/indirect/a3c16d09386067d9d4f30aa267b5ba4413a1a51bba1070d8e60b0ef8f1b22df9"> </div></td> <td> <p>Each initial submission is assigned to a <em><i>PLOS Medicine</i></em> staff editor for an assessment of scope and quality.</p> <p>The professional editor and Academic Editor will promptly assess the manuscript and will decide if it is likely to meet the requirement of providing a major advance in a particular field and describing a sufficient body of work to support that claim; if so, you’ll be invited to submit a Full Submission for Peer Review.</p></td> </tr> </tbody> </table> </div> <div data-section-id="2308"> <h2><a id="loc-peer-review" name="loc-peer-review" data-anchor-id="7824"></a>Peer Review</h2> </div> <div data-section-id="2309"> <table class="table-basic"> <tbody> <tr> <td style="vertical-align: top"> <div style="width: 70px"> <img alt="" class="img-default" src="/plosmedicine/indirect/e5f48b3b168b0e97dbb9afb4f38a2eb422211d3392d45d63ccd6b5b9276e2049"> </div></td> <td> <p>All articles, with the exception of Editorials and some Perspectives, are externally peer reviewed before a final decision is made about acceptance for publication. Expert reviewers are asked to assess the technical and scientific merits of the work. Where relevant, work presented in a manuscript undergoes a rigorous review of the statistical methods used.</p> <p><em><i>PLOS Medicine</i></em> uses single blind peer review. Reviewers remain anonymous unless they choose to identify themselves by signing their name to their review in our submission system.</p></td> </tr> </tbody> </table> </div> <div data-section-id="2313"> <h2><a id="loc-editorial-decisions" name="loc-editorial-decisions" data-anchor-id="7825"></a>Editorial Decisions</h2> </div> <div data-section-id="2314"> <table class="table-basic"> <tbody> <tr> <td style="vertical-align: top"> <div style="width: 70px"> <img alt="" class="img-default" src="/plosmedicine/indirect/a674bc6ad6ab8151c919468f107c5cd76ee6d087879809500cef228686857be2"> </div></td> <td> <p>In consultation together, the professional and Academic editors consider reviewer feedback and their own evaluations of the manuscript in order to reach a decision. The following decision types are available:</p> <ul> <li>Reject</li> <li>Major revision</li> <li>Minor revision</li> <li>Accept</li> </ul> <p>If after peer review a manuscript is considered potentially appropriate for <em>PLOS Medicine</em>, a major revision is generally requested. A minor revision is generally requested as a final step before acceptance.</p> <p>Manuscripts that are rejected generally do not fit the criteria outlined above in terms of originality, importance to the field, cross-disciplinary interest, or sound methodology.</p> <p>Decisions are communicated to the corresponding author in a formal letter, along with reviewer feedback and any other requirements from the journal office.</p></td> </tr> </tbody> </table> </div> <div data-section-id="551"> <h2><a data-anchor-id="4919" id="loc-revisions" name="loc-revisions"></a>Revisions</h2> </div> <div data-section-id="674"> <table class="table-basic"> <tbody> <tr> <td style="vertical-align: top"> <div style="width: 70px"> <img alt="" class="img-default" src="/plosmedicine/indirect/41aa303ca68b221fc6103fa068ac31ca153dcadad5d93c31ed56e5417de7d8ec"> </div></td> <td> <p>If the editors feel that your manuscript has the potential to be published, but requires changes, you’ll be invited to revise it.</p> <p>Revised manuscripts will be assessed by a professional editor and the same Academic Editor. Manuscripts that undergo major revision may require re-review or additional statistical review. There is no guarantee of acceptance after major revision.</p> <p><a href="/plosmedicine/s/revising-your-manuscript">Read more about revising your manuscripts</a></p></td> </tr> </tbody> </table> </div> <div data-section-id="552"> <h2><a data-anchor-id="4909" id="loc-accepted-manuscripts" name="loc-accepted-manuscripts"></a>Accepted Manuscripts</h2> </div> <div data-section-id="2319"> <table class="table-basic"> <tbody> <tr> <td style="vertical-align: top"> <div style="width: 70px"> <img alt="" class="img-default" src="/plosmedicine/indirect/2d30c4d72e061b8d8b56bf46c8d69ac88445ec0cd26798c3d30514b191310754"> </div></td> <td> <p>Once the final requirements are fulfilled, the journal office will send a formal accept decision, and your manuscript will move on to production.</p> <p><a href="/plosmedicine/s/accepted-manuscripts">Read more about accepted manuscripts</a>.</p></td> </tr> </tbody> </table> </div> <div data-section-id="2322"> <h2><a id="loc-peer-review-history" name="loc-peer-review-history" data-anchor-id="8145"></a>Peer Review History</h2> </div> <div data-section-id="2323"> <table class="table-basic"> <tbody> <tr> <td style="vertical-align: top"> <div style="width: 70px"> <img alt="" class="img-default" src="/plosmedicine/indirect/d36f5873e5e213f7edd2087e71ec1a2782b1435fb831f6d1f71985e5690197e0"> </div></td> <td> <p>PLOS offers accepted authors the opportunity to publish the peer review history of their manuscript alongside the final article. The peer review history package includes the complete editorial decision letter for each revision, with reviews, and your responses to reviewer comments, including attachments. If the peer reviewers have chosen to sign their reviews, their names will also appear.</p> <p>If your submission is accepted for publication, you’ll be invited to opt-in to publish the peer review history of your manuscript using a form in our submission system.</p> <p>Sharing peer review history enriches the scientific record, increases transparency and accountability, and helps to reinforce the validity of your research by displaying the thoroughness of the peer review process it has undergone.</p> <p>The journal reserves the right not to publish peer review history in special cases, for example, due to an ethical consideration, such as the inclusion of information about a vulnerable population.</p></td> </tr> </tbody> </table> </div> <div data-section-id="122"> <h2><a data-anchor-id="5140" id="loc-transferring-to-other-journals" name="loc-transferring-to-other-journals"></a>Transferring to Other Journals</h2> </div> <div data-section-id="1780"> <table class="table-basic"> <tbody> <tr> <td style="vertical-align: top"> <div style="width: 70px"> <img alt="" class="img-default" src="/plosmedicine/indirect/88119f7815792ff1dedfd8dd50fc88c9acc10f28f8878c04a3bcbb43e53ee124"> </div></td> <td> <p>Authors can request that original research submissions (with referee reports, if relevant) rejected from one PLOS journal be transferred to another PLOS journal for further consideration there. Manuscripts will never be transferred between the journals without an author’s consent.</p> <p>We trust that reviewers for any PLOS journal are willing to have their reviews considered by the editors of another PLOS journal.</p></td> </tr> </tbody> </table> </div> <div data-section-id="545"> <h2><a data-anchor-id="4883" id="loc-appeals" name="loc-appeals"></a>Appeals</h2> </div> <div data-section-id="548"> <table class="table-basic"> <tbody> <tr> <td style="vertical-align: top"> <div style="width: 70px"> <img alt="" class="img-default" src="/plosmedicine/indirect/fe713789f1531ac37a172adb8a74cedcd44503f408ea0ad3d8db087446a18fcb"> </div></td> <td> <p>Authors may submit a formal appeal to contest an editorial decision. Appeal requests must be made in writing to <a href="mailto:plosmedicine@plos.org">plosmedicine@plos.org</a> with the word “appeal” in the subject line, and would preferably include a completed <a href="/plosmedicine/s/file?id=c534/Appeal_Request_Form.docx">Appeal Request Form</a>. 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