Supporting implementation of Cochrane methods in complex communication reviews: resources developed and lessons learned for editorial practice and policy Cochrane Consumers and Communication La Trobe University RyanRebecca HillSophie 2019 Every healthcare encounter involves some form of communication and there is growing recognition that effective health communication is central to the delivery of safe, high-quality healthcare. Conversely, poor communication has a range of adverse consequences for those receiving healthcare and the systems delivering care, including elevated patient safety risks. Increasing understanding and documentation of the key role that good communication plays in healthcare design and delivery has meant there is growing demand from policy-makers and other decision-makers for evidence on the effects of health communication interventions – that is, how best to communicate. While systematic reviews of such interventions are fundamental to building this evidence base, such interventions and reviews are often highly complex and pose considerable challenges for authors and editors. In this paper, we describe our experience as a Cochrane editorial group identifying common issues in reviews of communication interventions and developing resources to support authors to better meet these challenges. Our analysis found that issues typically fell into one or more of the following three stages of the review process: understanding and applying systematic review methods (e.g. selecting outcomes for analysis); reporting the review’s methods (e.g. describing key decisions made in conducting the review); and interpreting the findings (e.g. incorporating quality of the evidence into findings of the review). We also found that common issues reflected both practical difficulties (such as the typically large size of reviews and disparate measures for outcomes) and conceptual challenges (for instance, the difficulties of identifying comparisons). While extensive advice for Cochrane systematic reviewers exists, this standardised advice does not cover all of the issues emerging for complex communication reviews. In response, we therefore developed a collection of resources, both general and targeted to specific methodological issues. Here, we describe the types of resources developed and the aims of these, the rationale for why we needed to fill specific gaps in existing advice, and reflect on the lessons for future editorial practice, policies and research in relation to the implementation of Cochrane review methods in the area of health communication.