How Literature Review of a PhD Dissertation Presents the State of the Art: Synthesis vs Listing

Quality of literature review is what majorly differentiates a PhD Thesis from an MS Thesis. The qualitative difference is in the digestion and synthesis of the existing work into a framework on which your research contribution and sequence can stand. This synthesis of existing work in the topic area should itself be worthy of a publication. Digestion of the existing papers is represented by a list of factors or parameters that you have identified on which you can compare and and contrast the existing literature. Not all parameters are relevant to all the papers. Hence, parameters are separated into different subsets. For each subset, a table can be constructed through which papers relevant to the subset parameters can be compared and contrasted. Analysis of these parameters provide you with the explanation of the gap or the problem area which is then articulated in the form of a problem statement.

Literature review chapter of your dissertation is written in a logical sequence that starts from a more general and broader review of the topic area which then progressively becomes more and more specific as the area gets narrow down  till it eventually funnels into your formal articulation of the problem statement.  The formalism of terminology used in the problem statement and the thesis statement requires precise definitions in the literature review that also encapsulates the research questions underpinning your research work. This exposition of the literature review is much different from the chaotic process through which you may have arrived at the articulation of your problem statement and thesis statement which is often being tweaked till the very last. It is at the very end that you realize the actual contribution you have made the significance of your research.

• Literature review differentates a PhD dissertation from an MS dissertation. It is not a listing but a synthesis
• It explains why your problem statement exists
• It explains why it is important for the problem to be solved. 
• It places your problem statement in the context of the existing literature. 
• It narrates in a story form using a logical sequence how you have drilled down to the problem statement. 
• It identifies during this drill down process all the essential terms used to define the problem formally in the problem statement and its solution, the thesis statement. 
• It analyzes the existing literature from the perspective of how it leads to your problem statement. 
• It develops all the essential “machinery” required to explain your contribution, its significance and the methodology that you would follow. That is, later chapters should not look like literature review.
• It is not written in the form or sequence in which you read the research papers. It is written in a form which makes the reader understands the problem.
• It must refer to only those papers that you have read. Second hand references from paper surveyed in research papers is unethical and unworthy of being part of the PhD literature review. 
• It is digestion of the food into enzymes (compounds) where the original papers (reactants) have lost their physical properties. 
• Digestion is in the form of tables or matrices where you decide what the column headings are and what the row headings are. Although row and column headings can be seen from other literature but their selection indicates the level of your digestion. The contents of the cell also indicate your digestion. 

[Work in Process]

References: 

1. Doing a literature review
2. Using a Synthesis Matrix

See Also: 

• Motivation: Why PhD?

What is PhD?