The literature review acknowledges the work of previous researchers, and in so doing, assures the reader that your work has been well conceived.
It is assumed that by mentioning a previous work in the field of study, that the author has read, evaluated, and assimiliated that work into the work at hand.
204-205): A systematic review: A traditional or narrative review summarizes different primary studies from which conclusions may be drawn into a holistic interpretation supplemented by the author's own experience, theories, and/or models: Whereas a meta-analysis is a way of testing a hypothesis, a meta-synthesis attempts to integrate results from a number of different but inter-related qualitative studies.
A literature review or narrative review is a type of review article.
The review should enumerate, describe, summarize, objectively evaluate and clarify this previous research.
It should give a theoretical base for the research and help you (the author) determine the nature of your research.
A narrow-scope literature review may be included as part of a peer-reviewed journal article presenting new research, serving to situate the current study within the body of the relevant literature and to provide context for the reader.
In such a case, the review usually precedes the methodology and results sections of the work.