Once you have selected the most reliable and relevant studies you will need to pull all the findings together using textual or statistical methods.
A narrative synthesis uses a textual approach to analyse the relationships within and between studies and gives an overall assessment of the robustness of the evidence for the effectiveness of a specific intervention.
A meta-analysis is the statistical combination of results from two or more separate studies. This gives an overall statistic (together with its confidence interval) that summarizes the effectiveness of an experimental intervention compared with a comparator intervention.
PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) provides a structured approach to reporting systematic reviews (and meta-analyses). There is a checklist outlining the sections to include in your report, and a flow diagram to record the number of records retained at each step in the review process.
Current PRISMA flow diagram templates
A new version of the PRISMA guidelines and flow diagram was published in 2020. There are now four templates to choose from:
The PRISMA flow diagram used prior to 2020 was simpler and may be more suitable for undergraduate and Masters' level systematic reviews (check with your supervisor which version they would like you to use).
See the following site for more information about PRISMA including the checklist: