What Is a Literature Review?
A literature review is a critical analysis of existing research on your dissertation topic. It is not simply a summary of what others have written; rather, it evaluates, synthesises, and organises previous studies to establish the context and justification for your own research. Learning how to write a literature review is one of the most important skills you will develop during your degree, as it forms the foundation of your entire dissertation.
In UK universities, the literature review typically forms its own chapter in your dissertation and accounts for approximately 25-30% of your total word count. It demonstrates to your examiners that you have a thorough understanding of your research area and can engage critically with academic sources.
Purpose of a Literature Review in Your Dissertation
The literature review serves several crucial purposes in your dissertation. First, it establishes the theoretical and conceptual framework for your research by identifying the key theories, models, and concepts relevant to your topic. Second, it demonstrates your knowledge of the field and your ability to critically engage with academic sources. Third, and most importantly, it identifies a gap in the existing research that your study aims to address.
Without a clear gap in the literature, your research lacks justification. The literature review builds the argument for why your study is needed by showing what has been done before and what remains unanswered. This gap becomes the foundation for your research questions and objectives.
Step 1: Define Your Scope and Search Strategy
Before you begin reading, define the scope of your literature review. What time period will you cover? What geographical focus will you have? What types of sources will you include? Establishing clear boundaries prevents you from being overwhelmed by the volume of available literature and keeps your review focused on your research questions.
Develop a systematic search strategy using academic databases such as Google Scholar, JSTOR, PubMed, Web of Science, and your university library catalogue. Use a combination of keywords related to your topic and Boolean operators (AND, OR, NOT) to refine your results. Keep a record of your search terms and the databases you used, as some universities require you to report your search strategy in the methodology chapter.
Start with recent review articles and seminal works in your field, then follow the reference lists of these papers to find additional relevant sources. This snowball technique helps you identify the most important studies and ensures you do not miss key contributions to the debate.
Step 2: Evaluate and Select Your Sources
Not every source you find will be suitable for your literature review. Evaluate each source for its relevance, credibility, methodology, and contribution to your topic. Prioritise peer-reviewed journal articles, as these have been vetted by experts in the field. Books, conference papers, and reports from reputable organisations can also be valuable.
Be cautious with sources that are outdated (unless they are seminal works), published in predatory journals, or based on weak methodology. Aim for a balance of recent research (within the last five to ten years) and foundational studies that have shaped the field. For an undergraduate dissertation, 30 to 50 sources is typically sufficient; masters dissertations may require 50 to 80, and PhD theses can include over 200.
Step 3: Organise Your Literature Thematically
One of the most common mistakes students make is organising their literature review chronologically or source by source. A much more effective approach is to organise it thematically, grouping sources by topic, methodology, or argument. This demonstrates your ability to identify patterns and connections across the literature.
Create a concept map or table that groups your sources by theme. Identify the main arguments, debates, and areas of agreement or disagreement. Consider how different studies relate to each other and to your research questions. This thematic organisation will form the structure of your literature review, with each theme becoming a section or subsection.
For example, if you are researching the impact of social media on student mental health, your themes might include: prevalence of social media use among students, theoretical models linking social media to wellbeing, positive effects of social media, negative effects, and moderating factors such as usage patterns and individual differences.
Step 4: Write Critically, Not Descriptively
Critical analysis is what separates a first-class literature review from an average one. Descriptive writing simply reports what each author said; critical writing evaluates, compares, and synthesises their arguments. For every source you discuss, consider its strengths and weaknesses, the quality of the evidence, and how it relates to other studies in your review.
Use critical language such as: “While Smith (2020) argues that… this finding is contradicted by Jones (2021), whose larger sample size and more rigorous methodology suggest that…” This demonstrates your ability to weigh evidence and form your own informed position. Avoid over-reliance on direct quotations; paraphrase and synthesise instead.
Each paragraph should make a clear point, supported by evidence from multiple sources where possible. Avoid dedicating entire paragraphs to a single study unless it is a particularly important or seminal piece of work. Synthesising multiple sources into a single paragraph shows a higher level of critical thinking.
Step 5: Structure Your Literature Review
A well-structured literature review follows a funnel approach, starting broad and narrowing down to your specific research focus. Begin with an introduction that outlines the scope and purpose of your review. Then present your themes in a logical order, from the most general to the most specific. End with a summary that identifies the gap your research will address.
Use clear subheadings to guide the reader through your review. Each section should flow logically into the next, with transition sentences that link themes together. The final paragraph of your literature review is crucial, as it should clearly state the gap in the literature and explain how your study will address it, leading naturally into your methodology chapter.
Common Literature Review Mistakes to Avoid
Several pitfalls can undermine the quality of your literature review. Avoid being purely descriptive without offering critical analysis. Do not try to include every source you have read; be selective and focus on the most relevant and high-quality studies. Ensure you include sources that contradict your hypothesis, as ignoring opposing evidence weakens your credibility.
Other common mistakes include relying too heavily on secondary sources, failing to identify a clear gap, and poor organisation that makes it difficult for the reader to follow your argument. Plagiarism, whether intentional or accidental, is another serious concern. Always cite your sources properly and use a reference management tool such as Mendeley, Zotero, or EndNote to keep track of your references.
Literature Review Examples and Templates
Examining published literature reviews in your field can provide valuable examples of structure, critical analysis, and writing style. Look at review articles published in leading journals, as well as dissertations from previous students at your university (often available through your library’s institutional repository).
A basic literature review template follows this structure: introduction (purpose, scope, and organisation), thematic sections (each with a clear focus and critical analysis), and conclusion (summary of key findings, identification of the gap, and link to your research). Adapt this template to suit your specific topic and research questions.
If you are struggling with your literature review, professional dissertation writing services can help you develop a comprehensive and critically engaging review that meets your university’s standards.
Frequently Asked Questions
How long should a literature review be? For an undergraduate dissertation, the literature review is typically 2,000 to 3,000 words. Masters dissertations usually require 4,000 to 6,000 words, while PhD literature reviews can be 10,000 to 15,000 words or more.
How many sources should I include? As a general guide, include 30 to 50 sources for an undergraduate dissertation, 50 to 80 for a masters, and 150 or more for a PhD. Focus on quality and relevance rather than quantity.
Should I include sources that contradict my argument? Yes. Including and critically evaluating opposing viewpoints strengthens your literature review by demonstrating balanced academic engagement and critical thinking skills.
What is the difference between a literature review and an annotated bibliography? An annotated bibliography summarises individual sources separately, while a literature review synthesises and critically analyses sources thematically to build a coherent argument and identify gaps in the research.