Umbrella Reviews

​This book is an ideal guide to umbrella reviews, overviews of reviews, and meta-epidemiologic studies for evidence synthesis. Research is conducted at different levels: primary research consists of original studies while secondary research comprises qualitative reviews, systematic reviews, and meta-analyses. Recently, a novel further level of research has been introduced, based on the analysis and pooling of reviews and meta-analysis. This book is the first to focus solely on this new type of r