A systematic review is a methodical and comprehensive literature synthesis focused on a well-formulated research question. Its aim is to identify and synthesize all of the scholarly research on a particular topic, including both published and unpublished studies. Systematic reviews are conducted in an unbiased, reproducible way to provide evidence for practice and policy-making, as well as to identify gaps in the research. Systematic reviews may also include a meta-analysis, a more quantitative process of synthesizing and visualizing data retrieved from various studies.
Systematic reviews are much more time-intensive than traditional literature reviews and usually require a multi-person research team. See this PredicTER tool to get a sense of a systematic review timeline. Before embarking on a systematic review, it's important to determine whether the body of literature warrants one and to clearly identify your reasons for conducting a systematic review. For a list of other types of evidence synthesis projects, see the next tab.
There are a number of reporting standards for systematic reviews. These can serve as guidelines for protocol and manuscript preparation and journals may require that these standards are followed for systematic reviews.
The PRISMA flow diagram depicts the flow of information through the different phases of a systematic review. It maps out the number of records identified, included and excluded, and the reasons for exclusions. Most systematic reviews include a PRISMA flow diagram to track the search, screening and selection process. See below for resources to help you generate your own PRISMA flow diagram.