Background: Publication and other reporting biases may pose serious threats to the validity of systematic reviews. Over the last few years there has been growing support for a move towards greater transparency with improved access to regulatory submission documents including clinical study reports (CSRs) - which provide much more data than are included in published articles. Using CSRs and other regulatory documents, either together with or instead of more traditional sources, has the potential to change the future of Cochrane Reviews of pharmaceutical interventions.

Objectives: To draft interim guidance to help Cochrane authors decide whether to include data from CSRs and other regulatory documents in Cochrane Reviews.

Methods: Guidance will be based upon the research literature on reporting biases and their impact on evidence synthesis and on exploration of indicators or ‘triggers’ that might indicate when it is most important to access and use this type of data. In addition to the research literature, guidance will be informed by the results of a survey of review authors regarding their use of CSRs and other regulatory documents in their reviews.

Results: We will provide an update on the progress of this Cochrane project, present a summary of the literature in this area along with a summary of the history and evolution of the data access movement. We will also present details of our planned survey of review authors and intend to identify barriers and facilitators to including data from regulatory material in Cochrane Reviews.

Conclusions: After addressing the question of ‘when’ to include CSRs in Cochrane Reviews we need to address the next pressing question for authors of ‘how’ to include CSRs in Cochrane Reviews.

Funding: This project is funded in part by a Cochrane Methods Innovation Fund award.