In the making of one’s research paper, one must have a literature review and/or synthesis to be able to have an overview about their topic and the results surrounding their hypothesis. However, apart from the similarities between the literature review and the synthesis, they have quite the differences from each other. Furthermore, the literature review and the synthesis are immensely important in having a complete research paper as it helps the researcher in building up information about his/her hypothesis.
Firstly, the literature review includes surveys, books, scholarly articles, and any other source related to the topic that is being researched as its purpose is to show an overall image of all the sources that one went through while researching for that topic, and it also helps to emphasize that your research fit into a bigger field or study. The literature review has a lot of types; to start with, the first type is the argumentative review, whereas all the sources used focus on either supporting or refuting a certain point. The second type is integrative review, which is made to review, critique, and synthesize the sources in an integrative way that new perspectives can be developed from this type of literature review. The third type is the historical review, which usually traces the first time a problem, phenomena, or concept emerged, and then it traces its development throughout history.
The fourth type, is the methodological review, which focuses on the methods through which the researchers were able to gather the data for their researches; such as, substantive fields, research approaches, data collection, and analysis techniques. The fifth type is the systematic review which is an overview of existing data about a specific research question. Finally, the sixth and final type, is the theoretical review. This review helps emphasize the theories that exist, the relationship between them, and the level in which those theories have been explored.
On the other hand, a synthesis combines the results of numerous primary research studies that had tested the same hypothesis as the researcher, and that would help generate new findings by merging and comparing the results of those primary researches. The synthesis can be done in several ways; like, Meta-analysis which is a statistical analysis that combines the findings of numerous scientific studies, and uses all the studies made about the same hypothesis and uses an approach from statistics to derive a pooled estimate closest to the unknown common truth. Meta-analysis is usually used in quantitative research synthesis. Another method is the narrative synthesis which goes beyond just narrating the primary research found, it compares and contrasts studies and explores relation between studies. The last method is meta-ethnography which is made to combine data studies, especially ethnographic data, and tries to relate concepts within studies to other studies. Those two methods are usually used for qualitative research.
All in all, both the literature review and the synthesis are important tools for research as they both provide an overall and a deeper look into the sources relating to the researcher’s topic, but they are different in regards of the sources that they include and the methods or the types that are used in them as the literature review reviews all types of sources, while the synthesis includes primary research only. The literature review and the synthesis help the researcher in both getting an overview of the field in which they are researching in and in investigating other studies that were aimed at the same hypothesis as the researcher which would enable him/her to have more wholesome view of their own topic and research question.