Methodologies and methods to conduct research syntheses are dynamic and evolving. Over the past seven years, the JBI program of synthesis science has grown from novel methodologies to tackle three key types of questions (effects of interventions, experiences with interventions, and costs of interventions) to the 11 diverse methodologies and methods currently presented in the JBI Manual for Evidence Synthesis,1 which are designed to address a full range of questions and types of evidence. In this issue of JBI Evidence Synthesis, we are pleased to present our first issue with a focus on synthesis methodology. The articles presented here introduce a new section of the journal, which will be a feature of future volumes.

Headlining our first spotlight on synthesis methodology is the JBI approach to mixed methods reviews. The feature article by Stern et al.2 presents the development and key features of this type of systematic review, which continues to gain prominence due to its ability to accommodate both quantitative and qualitative evidence in a single integrated approach. This allows for a more complete picture of the evidence to assist in complex decision-making. The unique element of these types of review is that the nature of the questions posed directs the approach the reviewer needs to take in synthesis and integration. These are described in the two protocols3,4 undertaken by these same authors, which will test the two distinct approaches that are described.1 In addition, a scoping exercise of methods employed to date to address questions related to barriers and facilitators to implementing best practice interventions in health care will further inform the application of methodology.5 The convergent integrated approach is forwarded as the preferred strategy to addressing questions exploring barriers and facilitators in health care2; this project will determine which methodologies and methods have historically dominated this domain of research.

Importantly, this month's issue also includes the much anticipated update to the methodological guidance that underpins JBI scoping reviews.6 The popularity of this type of evidence synthesis is evidenced by the number of submissions for scoping review projects received by the journal and their dominance of our table of contents throughout the current volume in 2020. One important feature of the updated guidance is reinforcement of the rationale for conduct of a scoping review to ensure authors are using this methodology appropriately and where it is best suited - that is, mapping and providing a view of the landscape of research (or facets) in a particular area. The updated guidance also provides useful and much-needed examples of diverse ways to present the results, or "map of the data," in a JBI scoping review.6 This is where the art of synthesis, and the facilitation and ease of use of the evidence and review product come to the fore.

These methods are presented in other manuscripts in the current issue, which also serve to highlight the utility of scoping reviews when establishing the lay of the land and current position with regard to methods of research synthesis. In addition to the project by Lizarondo et al.,5 another notable example is that of Whitehorn et al.7 who scope the literature to provide a comprehensive overview and assessment of current approaches to the development of evidence summaries, rapid syntheses, and other derivative products to facilitate the uptake of evidence to inform health care policy and practice.

The current issue also includes, to the best of our knowledge, the protocol for the first "living" scoping review project to be undertaken, characterized by regular database searching to identify and add new eligible studies.8

The journal will continue to be the natural avenue for the dissemination and publication of the work of JBI's international methodology groups focused on synthesis. We invite authors with well-conducted research that investigates and furthers the science of conduct and reporting of research syntheses and systematic reviews to submit their articles to JBI Evidence Synthesis.

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