Evidence synthesis

• Systematic review - aims to identify and formally evaluate all the studies addressing a clearly defined research question using methods that are set out in advance (in a protocol).
• Meta-analysis - evidence syntheses may include a statistical analysis that combines individual study results.
• Integrative review - similar to systematic review but assimilates various data from various research designs (both quantitative and qualitative) as well as other documents such as discussion papers and policy documents.
• Umbrella review (Overview of reviews) - reviews all the systematic reviews or meta-analyses on a topic or intervention.
• Rapid review - when an answer is needed quickly, researchers can use streamlined methods to produce a rapid review.
• Scoping reviews or production of an evidence map – these can be carried out if we want to know what studies exist without looking in detail at their findings.

Cochrane Evidence Synthesis and Methods is an official journal of Cochrane. The journal aim is to improve how we publish and share evidence synthesis in health and social care. To do this, they follow Cochrane’s philosophy for transparency, integrity, and independence. They accept a wide range of article types including methods research, scoping reviews, rapid reviews, and evidence gap maps.

Cochrane's handbook chapter 5 provides excellent information on conducting an overview of reviews or meta-analyses.