In the methodology section of a systematic review, it's important to clearly explain the criteria for including and excluding studies. In this section it's also recommended to outline the search strategy concisely and in greater detail within a separate search template provided in an appendix. The study selection process should be documented using a PRISMA flow diagram.
Preferred Reported Items for Systematic Reviews and Meta-Analyses (PRISMA), is an international guideline for how a systematic review should be reported.
PRISMA Statement - Guidelines for Reporting Systematic Reviews
A common practice in systematic reviews is to use a flow diagram, like a PRISMA flow diagram, to summarize the process of searching for and evaluating literature. This diagram breaks down stages including identification, screening, eligibility, and inclusion, giving a clear overview of the number of studies included and excluded at each stage.