You may want to think about criteria that will be used to select articles for your literature review based on your research question. These are commonly known as inclusion criteria and exclusion criteria. Be aware that you may introduce bias into the final review if these are not used thoughtfully.
Inclusion criteria are the elements of an article that must be present in order for it to be eligible for inclusion in a literature review. Some examples are:
Exclusion criteria are the elements of an article that disqualify the study from inclusion in a literature review. Some examples are: