The structure of a literature review should include the following:
The critical evaluation of each work should consider:
While conducting a review of the literature, maximize the time you devote to writing this part of your paper by thinking broadly about what you should be looking for and evaluating. Review not just what the articles are saying, but how are they saying it.
Some questions to ask:
Now, that you have found articles based on your research question you can appraise the quality of those articles. These are resources you can use to appraise different study designs.
Centre for Evidence Based Medicine (Oxford)
University of Glasgow
"AFP uses the Strength-of-Recommendation Taxonomy (SORT), to label key recommendations in clinical review articles."