Cochrane Overviews of Reviews (Overviews) compile evidence from multiple systematic reviews into a single accessible and usable document. They are intended primarily to synthesize multiple Cochrane Reviews addressing a set of related interventions, populations, outcomes, or conditions, although other published non-Cochrane reviews may also be included. Cochrane Overviews provide the reader with a quick and comprehensive guide to reviews relevant to a specific decision. Overviews are aimed at decision makers, such as clinicians, policy makers, or informed consumers, who are accessing the CDSR for evidence on a specific problem. Overviews of Reviews on the effects of interventions are addressed in detail in Chapter 22 (see Section 22.1).
An overview of systematic reviews of diagnostic test accuracy (DTA Overview) can be used to synthesize and compare findings from a related set of test accuracy reviews. For example, an overview might bring together and compare the findings of separate reviews of alternative tests used to diagnose the same condition at the same point in the patient pathway. DTA Overviews also have a role in evaluating the accuracy of tests for the detection of closely related target conditions (particularly when they form part of a set of differential diagnoses), and in evaluating the performance of the same test across different settings. DTA Overviews are best planned when commencing on a portfolio of related individual systematic reviews, and plans for incorporation in a DTA Overview should be mentioned in the protocols of the individual reviews.