Evidence syntheses systematically compile and analyze information from multiple sources to support health care decision making. As many different types of questions need to be answered in health care, different evidence synthesis types have emerged. In this article, we introduce the most common types of evidence synthesis. We discuss the aims, key methodological features and illustrative examples of different evidence synthesis types and modes, drawing on our work with the Evidence Synthesis Taxonomy Initiative. Evidence synthesis types include systematic reviews, overviews of reviews, qualitative evidence syntheses, mixed-methods reviews, and 'big picture reviews' (scoping reviews, mapping reviews, and evidence gap maps). Additionally, we focus on rapid and living reviews as modes and how they can be applied to different evidence synthesis types. It is essential for clinicians and researchers to understand the main types of evidence synthesis to choose the most suitable method for addressing a specific health-related question.
Nußbaumer-Streit et al. (Mon,) studied this question.