There may be instances when the public would benefit from the simultaneous publication of a Cochrane Review in both the Cochrane Database of Systematic Reviews (CDSR) and another journal. The journal is likely to be a specialist publication (reaching a specialist audience) or published in a language other than English (reaching a new audience). Simultaneous publication of a Cochrane Review may be discussed with the Cochrane Review Group (CRG) at any stage of the Cochrane Review development process, and ideally as soon as the authors consider this possibility. All decisions concerning co-publication will reflect the input and contribution of the CRG staff, editors, and peer reviewers. This contribution should also be acknowledged in any co-published version of the Cochrane Review.

Before proceeding along this route, authors must consider the following.

• The journal editor may consider the publication to be redundant (duplicate) publication, that is, “publication of a paper that overlaps substantially with one already published in print or electronic media” (ICMJE recommendations on overlapping publications; accessed 22 August 2018). This could potentially lead to limitations being imposed on publication of the Cochrane Review in the CDSR, which are unacceptable to Cochrane.
• Authors of published Cochrane Reviews have granted Cochrane an exclusive licence for publication for the Cochrane Review, meaning that the Cochrane Review cannot be published elsewhere without permission, and the journal editor needs to be aware of this.

To initiate this process, authors should first contact the relevant Managing Editor of the CRG for permission (using the 'Permission to co-publish' form (Permission to co-publish). The CRG will refer each case to the Cochrane Editorial & Methods Department (contact emd@cochrane.org and ensure that the subject line of your email clearly states "Co-publication query). The authors, the CRG and the journal will all be required to follow the steps outlined in the section Co-publication process.