Q. What is a systematic review?

A systematic review is a type of evidence synthesis project. According to the JBI, systematic reviews "aim to provide a comprehensive, unbiased synthesis of many relevant studies in a single document using rigorous and transparent methods." Systematic reviews attempt to uncover all (or as much as possible) evidence in relation to a research question. Systematic reviews are unique from other review types because they try to answer a very specific clinical or research question. 

For example, one study on the effectiveness of metformin in the treatment of type 2 diabetes is limited by its population size, demographics, and other factors. A systematic review attempts to find ALL studies (based on specific criteria) about the effectiveness of metformin in the treatment of type 2 diabetes and to synthesize ALL of the findings. This creates more powerful evidence that can be relied upon to make clinical decisions.

The JBI lists the following as the steps for a systematic review:

1. Formulating a review question
2. Defining inclusion and exclusion criteria
3. Locating studies through searching
4. Selecting studies for inclusion
5. Assessing the quality of studies
6. Extracting data
7. Analyzing and synthesizing the relevant studies
8. Presenting and interpreting the results, potentially including a process to establish certainty in the body of evidence (through systems such as GRADE)