Conducting a literature review enables you to demonstrate your understanding and knowledge of the existing work within your field of research. Doing so allows you to identify any underdeveloped areas or unexplored issues within a specific debate, dialogue or field of study. This, in turn, helps you to clearly and persuasively demonstrate how your own research will address one or more of these gaps.
Please note: this guide is not specific to any one discipline. The literature review can vary depending on the nature of the research and the expectations of the school or department. Please adapt the following advice to meet the demands of your dissertation and the expectations of your school or department. Consult your supervisor for further guidance; you can also check out Writing Across Subjects guide.
As part of the Writing the Dissertation series, this guide covers the most common expectations for the literature review chapter, giving you the necessary knowledge, tips and guidance needed to impress your markers! The sections are organised as follows:
The literature review of a dissertation gives a clear, critical overview of a specific area of research. Our main Writing the Dissertation - Overview and Planning guide explains how you can refine your dissertation topic and begin your initial research; the next tab of this guide, 'Process', expands on those ideas. In summary, the process of conducting a literature review usually involves the following:
Writers should keep in mind that the phrase 'literature review' refers to two related, but distinct, things:
This distinction is vital to note because every dissertation requires the writer to engage with and consider existing literature (i.e., to undertake the active process). Research doesn't exist in a void, and it's crucial to consider how our work builds from or develops existing foundations of thought or discovery. Thus, even if your discipline doesn't require you to include a chapter titled 'Literature Review' in your submitted dissertation, you should expect to engage with the process of reviewing literature.
Not all literature reviews are the same. For example, in many subject areas, you are expected to include the literature review as its own chapter in your dissertation. However, in other subjects, the dissertation structure doesn't include a dedicated literature review chapter; any literature the writer has reviewed is instead incorporated in other relevant sections such as the introduction, methodology or discussion.
For this reason, there are a number of questions you should discuss with your supervisor before starting your literature review. These questions are also great to discuss with peers in your degree programme. These are outlined in the table below (see the Word document for a copy you can save and edit):
| How long is the literature review expected to be? Is there a word limit? |
| Will the literature review be included in the final dissertation? |
| How many sources should be included? (This may be a rough number as opposed to an exact amount.) |
| What kinds of sources should you be looking at (e.g. books, published articles, data sets, market reports, governmental or NHS guidelines, creative works, etc.)? |
| Will you need library support/training to access any of the sources required? |
| How should the review be structured (e.g. should you include subheadings, is thematic/subtopic grouping or chronological grouping preferable)? |
| How critical should your engagement with the sources be? (Some disciplines feature literature reviews that are more expository or descriptive in nature.) |
| Are you required to keep a technical record of your search strategies? |
| Are there any other requirements specific to your discipline/research area? |
Conducting a literature review requires you to stay organised and bring a systematic approach to your thinking and reading. Scroll to continue reading, or click a link below to jump immediately to that section:
The first step of any research project is to select an interesting topic. From here, the research phase for your literature review helps to narrow down your focus to a particular strand of research and to a specific research question. This process of narrowing and refining your research topic is particularly important because it helps you to maintain your focus and manage your material without becoming overwhelmed by sources and ideas.
Try to choose something that hasn’t been researched to death. This way, you stand a better chance of making a novel contribution to the research field.
Conversely, you should avoid undertaking an area of research where little to no work has been done. There are two reasons for this:
Researching and writing a literature review is partly about demonstrating your independent research skills. Your supervisor may have some tips relating to your discipline and research topic, but you should be proactive in finding a range of relevant sources. There are various ways of tracking down the literature relevant to your project, as outlined below.
One thing you don’t want to do is simply type your topic into Google and see what comes up. Instead, use Library Search to search the Library’s catalogue of books, media and articles.
Online training for 'Using databases' and 'Finding information' can be found here. You can also use the Library's subject pages to discover databases and resources specific to your academic discipline.
As well as making use of library resources, it can be helpful to discuss your work with students or academics working in similar areas. Think about attending relevant conferences and/or workshops which can help to stimulate ideas and allows you to keep track of the most current trends in your research field.
Finding relevant literature can, at times, be a long and slightly frustrating experience. However, one good source can often make all the difference. When you find a good source that is both relevant and valuable to your research, look at the material it cites throughout and follow up any sources that are useful. Also check if your source has been cited in any more recent publications.
Think of the bibliography/references page of a good source as a series of breadcrumbs that you can follow to find even more great material.
It is very important to be selective when choosing the final sources to include in your literature review. Below are some of the key questions to ask yourself:
Once you have selected a source to use in your literature review, it is useful to make notes on all of its key features, including where it comes from, what it says, and what its main strengths and weaknesses are. This way you can easily re-familiarise yourself with a source without having to re-read it. Keeping an annotated bibliography is one way to do this.
Alternately, below is a table you can copy and fill out for each source (see the Word document to save an editable copy for yourself). Software such as EndNote also allows you to keep an electronic record of references and your comments on them.
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Field
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Comment |
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Full reference
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Author’s background and their other notable works |
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Intended audience
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Brief summary of the text
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Main argument
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Strengths of the source
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Weaknesses/limitations of the source
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Useful quotes (and page numbers) |
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As we explored in the 'Getting Started' tab, the literature review is both a process you follow and (in most cases) a written chapter you produce. Thus, having engaged the review process, you now need to do the writing itself. Please continue reading, or click a heading below to jump immediately to that section.
The structure of the final piece will depend on the discipline within which you are working as well as the nature of your particular research project. However, here are a few general pieces of advice for writing a successful literature review:
There are several different ways to structure the literature review chapter of your dissertation. Two of the most common strategies are thematic structure and chronological structure (the two of which can also be combined). However you structure the literature review, this section of the dissertation normally culminates in identifying the research gap.
Variations of this structure are followed in most literature reviews. In a thematic structure, you organise the literature into groupings by theme (i.e., subtopic or focus). You then arrange the groupings in the most logical order, starting with the broadest (or most general) and moving to the narrowest (or most specific).
To plan a thematic structure structure, it helps to imagine your themes moving down a funnel or inverted pyramid from broad to narrow. Consider the example depicted below, which responds to this research question:
What role did the iron rivets play in the sinking of the Titanic?
The topic of maritime disasters is the broadest theme, so it sits at the broad top of the funnel. The writer can establish some context about maritime disasters, generally, before narrowing to the Titanic, specifically. Next, the writer can narrow the discussion of the Titanic to the ship's structural integrity, specifically. Finally, the writer can narrow the discussion of structural integrity to the iron rivets, specifically. And voila: there's the research gap!
The broad-to-narrow structure is intuitive for readers. Thus, it is crucial to consider how your themes 'nest inside' one another, from the broad to the narrow. Picturing your themes as nesting dolls is another way to envision this literature review structure, as you can see in the image below.
As with the funnel, remember that the first layer (or in this case, doll) is largest because it represents the broadest theme. In terms of word count and depth, the tinier dolls will warrant more attention because they are most closely related to the research gap or question(s).
The example above demonstrates a research project for which one major heading might suffice, in terms of outlining the literature review. However, the themes you identify for your dissertation might not relate to one another in such a linear fashion. If this is the case, you can adapt the funnel approach to match the number of major subheadings you will need.
In the three slides below, for example, a structure is depicted for a project that investigates this (fictional) dissertation research question: does gender influence the efficacy of teacher-led vs. family-led learning interventions for children with ADHD? Rather than nesting all the subtopics or themes in a direct line, the themes fall into three major headings.
The first major heading explores ADHD from clinical and diagnostic perspectives, narrowing ultimately to gender:
The second major heading explores ADHD within the classroom environment, narrowing to intervention types:
The final major heading articulates the research gap (gender differences in efficacy of teacher-led vs. family-led interventions for ADHD) by connecting the narrowest themes of the prior two sections.
Multi-funnel literature review structure by Academic Skills Service
To create a solid thematic structure in a literature review, the key is thinking carefully and critically about your groupings of literature and how they relate to one another. In some cases, your themes will fit in a single funnel. In other cases, it will make sense to group your broad-to-narrow themes under several major headings, and then arrange those major headings in the most logical order.
Some literature reviews will follow a chronological structure. As the name suggests, a review structured chronologically will arrange sources according to their publication dates, from earliest to most recent.
This approach can work well when your priority is to demonstrate how the research field has evolved over time. For example, a chronological arrangement of articles about artificial intelligence (AI) would allow the writer to highlight how breakthroughs in AI have built upon one another in sequential order.
A chronological structure can also suit literature reviews that need to capture how perceptions or understandings have developed across a period of time (including to the present day). For example, if your dissertation involves the public perception of marijuana in the UK, it could make sense to arrange that discussion chronologically to demonstrate key turning points and changes of majority thought.
The chronological structure can work well in some situations, such as those described above. That being said, a purely chronological structure should be considered with caution. Organising sources according to date alone runs the risk of creating a fragmented reading experience. It can be more difficult in a chronological structure to properly synthesize the literature. For these reasons, the chronological approach is often blended into a thematic structure, as you will read more about, below.
The structures of literature reviews can vary drastically, and for any given dissertation there will be many valid ways to arrange the literature.
For example, many literature reviews will combine the thematic and chronological approaches in different ways. A writer might match their major headings to themes or subtopics, but then arrange literature chronologically within the major themes identified. Another writer might base their major headings on chronology, but then assign thematic subheadings to each of those major headings.
When considering your options, try to imagine your reader or audience. What 'flow' will allow them to best follow the discussion you are crafting? When you are reading articles, what structural approaches do you appreciate in terms of ease and clarity?
The bulk of your literature review will explore relevant points of development and scholarly thought in your research field: in other words, 'Here is what has been done so far, thus here is where the conversation now stands'. In that way, you position your project within a wider academic discussion.
Having established that context, the literature review generally culminates in an articulation of what remains to be done: the research gap your project addresses. See the next tab for further explanation and examples.
The term research gap is intimidating for many students, who might mistakenly believe that every single element of their research needs to be brand new and fully innovative. This isn't the case!
The gap in many projects will be rather niche or specific. You might be helping to update or re-test knowledge rather than starting from scratch. Perhaps you have repeated a study but changed one variable. Maybe you are considering a much discussed research question, but with a lesser used methodological approach.
To demonstrate the wide variety of gaps a project could address, consider the examples below. The categories used and examples included are by no means comprehensive, but they should be helpful if you are struggling to articulate the gap your literature review has identified.
***Please note that the content of the example statements has been invented for the sake of demonstration. The example statements should not be taken as expressions of factual information.
Many dissertation research questions involve the study of a specific population. Those populations can be defined by nationality, ethnicity, gender, sexuality, socioeconomic class, political beliefs, religion, health status, or other factors. Other research questions target a specific geography (e.g. a country, territory, city, or similar). Perhaps your broader research question has been pursued by many prior scholars, but few (or no) scholars have studied the question in relation to your focal population or locale: if so, that's a gap.
The original contribution might involve examining something through a new lens. Theoretical framework refers, most simply, to the theory or theories a writer will use to make sense of and shape (i.e., frame) their discussion. Perhaps your topic has been analysed in great detail through certain theoretical lenses, but you intend to frame your analysis using a theory that fewer scholars have applied to the topic: if so, that's a gap.
The research gap might be defined by differences of methodology (see our Writing the Methodology guide for more). Perhaps your dissertation poses a central question that other scholars have researched, but they have applied different methods to find the answer(s): if so, that's a gap.
Absolutes such as never and always rarely apply in academia, but here is an exception: in academia, a single study or analysis is never enough. Thus, the gap you address needn't be a literal void in the discussion. The gap could instead have to do with replicability or depth/scope. In these cases, you are adding value and contributing to the academic process by testing emerging knowledge or expanding underdeveloped discussions.
Academia values up-to-date knowledge and findings, so another valid type of gap relates to elapsed time. Many factors that can influence or shape research findings are ever evolving: technology, popular culture, and political climates, to name just a few. Due to such changes, it's important for scholars in most fields to continually update findings. Perhaps your dissertation adds value by contributing to this process.
For example, imagine if a scholar today were to rely on a handbook of marketing principles published in 1998. As good as that research might have been in 1998, technology (namely, the internet) has advanced drastically since then. The handbook's discussion of online marketing strategies will be laughably outdated when compared to more recent literature.
This portion of the guide will cover some common missteps you should try to avoid in writing your literature review. Scroll to continue reading, or click a heading below to jump immediately to that section.
Trying to write your literature review before you have conducted adequate research is a recipe for panic and frustration. The literature review, more than any other chapter in your dissertation, depends upon your critical understanding of a range of relevant literature. If you have only dipped your toe into the pool of literature (rather than diving in!), you will naturally struggle to develop this section of the writing. Focus on developing your relevant bases of knowledge before you commit too much time to drafting.
As established above, a literature review does require a significant amount of reading. However, you aren't expected to review everything ever written about your topic. Instead, aim to develop a more strategic approach to your research. A strategic approach to research looks different from one project to the next, but here are some questions to help you prioritise:
While reviewing the literature, you might discover authors who disagree with your central argument or whose own findings contradict your hypothesis. Don't omit those sources: embrace them! Remember, the literature review aims to explore the academic dialogue around your topic: disagreements or conflicting findings are often part of that dialogue, and including them in your writing will create a sense of rich, critical engagement. In fact, highlighting any disagreements amongst scholars is a great way to emphasise the relevance of, and need for, your own research.
As shown in the funnel structure (see 'Structure' tab for more), a literature review often starts broadly and then narrows the dialogue as it progresses, ultimately bringing the reader to the dissertation's specific research topic (e.g. the funnel's narrowest point).
Within that structure, it's common for writers to miscalculate the scope required. They might open the literature review far too broadly, dedicating disproportionate space to developing background information or general theory; alternately, they might rush into the narrowest part of the discussion, failing to develop any sense of surrounding context or background, first.
It takes trial and error to determine the appropriate scope for your literature review. To help with this...
The illustration above shows a stairwell diagram of a dissertation that aims to analyse Stephen King's horror novel The Stand through the lens of a specific feminist literary theory.
The third step, therefore, represents a promising starting point: not too narrow, not too broad.
Above all else, a literature review needs to synthesize a range of sources in a logical fashion. In this context, to synthesize means to bring together, connect, weave, and/or relate. A common mistake writers make is failing to conduct such synthesis, and instead discussing each source in isolation. This leads to a disconnected structure, with each source treated like its own little 'island'. The island approach works for very few projects.
Some writers end up with this island structure because they confuse the nature of the literature review with the nature of an annotated bibliography. The latter is a tool you can use to analyse and keep track of individual sources, and most annotated bibliographies will indeed be arranged in a source-by-source structure. That's fine for pre-writing and notetaking, but to structure the literature review, you need to think about connections and overlaps between sources rather than considering them as stand-alone works.
If you are struggling to forge connections between your sources, break down the process into tiny steps:
The above exercise is not meant to suggest that you can only write one sentence per source: you can write more than that, of course! The exercise is simply designed to help you start synthesizing the literature rather than giving each source the island treatment.
A: Let's boil it down to three key points...
A: It's normal to struggle with identifying a research gap. This can be particularly true if you are working in a highly saturated research area, broadly speaking: for example, if you are studying the links between nutrition and diabetes, or if you are studying Shakespeare.
The 'What to Avoid' tab explained that miscalculating the scope is a common mistake in literature reviews. If you are struggling to identify your gap, scope might be the culprit, particularly if you are working in a saturated field. Remember that the gap is the narrowest part of the funnel, the smallest nesting doll, the lowest step: this means your contribution in that giant academic conversation will need to be quite 'zoomed in':
This is not a valid gap → Analysing Shakespeare's sonnets.
This might be a valid gap → Conducting an ecocritical analysis of the visual motifs of Shakespeare's final five procreation sonnets (e.g. sonnets number thirteen to seventeen).
In the above example, the revised attempt to articulate a gap 'zooms in' by identifying a particular theoretical lens (e.g. ecocriticism), a specific convention to analyse (e.g. use of visual motifs), and a narrower object (e.g. five sonnets rather than all 150+). The field of Shakespeare studies might be crowded, but there is nonetheless room to make an original contribution.
Conversely, it might be difficult to identify the gap if you are working not in a saturated field, but in a brand new or niche research area. How can you situate your work within a relevant academic conversation if it seems like the 'conversation' is just you talking to yourself?
In these cases, rather than 'zooming in', you might find it helpful to 'zoom out'. If your topic is niche, think creatively about who will be interested in your results. Who would benefit from understanding your findings? Who could potentially apply them or build upon them? Thinking of this in interdisciplinary terms is helpful for some projects.
Tip: Venn diagrams and mind maps are great ways to explore how your research connects to, and diverges from, the existing literature.
A: This question is risky to answer because the variations between individual projects and disciplines make it impossible to provide a universal answer. The fact is that one dissertation might have 50 more references than another, yet the two projects could be equally rigorous and successful in fulfilling their research aims.
With that warning in mind, let's consider a 'standard' dissertation of around 10K words. In that context, referencing 30 to 40 sources in your literature review tends to work well. Again, this is not a universally accurate rule, but a ballpark figure for you to contemplate. If the 30 to 40 estimate seems frighteningly high to you, do remember that many sources will be used sparingly rather than being mulled over at length. Consider this example:
In British GP practices, pharmaceutical treatment is most often prescribed for Health Condition XYZ (Carlos, 2019; Jones, 2020; Li, 2022). Lifestyle modifications, such as physical exercise or meditation practices, have only recently...
When writing critically, it's important to validate findings across studies rather than trusting only one source. Therefore, this writer has cited three recent studies that agree about the claim being made. The writer will delve into other sources at more length, but here, it makes sense to cite the literature and move quickly along.
As you search the databases and start following the relevant trails of 'research bread crumbs', you will be surprised how quickly your reference list grows.
A: Think creatively about the literature you are using and engaging with. A good start is panning out to consider your topic more broadly: you might not identify articles that discuss your exact topic, but what can you discover if you shift your focus up one level?
Imagine, for example, that Norah is researching how artificial intelligence (AI) can be used to provide dance instruction. She discovers that no one has written about this topic. Rather than panicking, she breaks down her research question into its component parts to consider what research might exist.
In summary, don't panic if you can't find research on your exact question or topic. Think through the broader context and parallel ideas, and you will soon find what you need.
A: This is a great question. Whilst many disciplines dictate that your dissertation should include a chapter called Literature Review, not all subjects follow this convention. Those subjects will still expect you to incorporate a range of external literature, but you will nest the sources under different headings.
For example, some disciplines dictate an introductory chapter that is longer than average, and you essentially nest a miniature literature review inside the introduction, itself. Although the writing is more condensed and falls under a subheading of the introduction, the techniques and principles of writing a literature review (for example, moving from the broad to the narrow) will still prove relevant.
Some disciplines include chapters with names like Background, History, Theoretical Framework, etc. The exact functions of such chapters differ, but they have this in common: reviewing literature. You can't provide a critical background or history without synthesizing external sources. To illustrate your theoretical framework, you need to synthesize a range of literature that defines the theory or theories you intend to use.
Therefore, as stated earlier in this guide, you should be prepared to review and synthesize a range of literature regardless of your discipline. You can tailor the purpose of that synthesis to the structure and demands of writing in your subject area.
A: The short answer is 'no' - there are some situations in which it is okay to use a source in your discussion chapter that you didn't integrate into your literature review chapter.
Imagine, for example, that your study produced a surprising result: a finding that you didn't anticipate. To make sense of that result, you might need to conduct additional research. That new research will help you explain the unexpected result in your discussion chapter.
More often, however, your discussion will draw on, or return to, sources from your literature review. After all, the literature review is where you paint a detailed picture of the conversation surrounding your research topic. Thus, it makes sense for you to relate your own work to that conversation in the discussion.
The literature review provides you an opportunity to engage with a rich range of published work and, perhaps for the first time, critically consider how your own research fits within and responds to your academic community. This can be a very invigorating process!
At the same time, it's likely that you will be juggling more academic sources than you have ever used in a single writing project. Additionally, you will need to think strategically about the focus and scope of your work: figuring out the best structure for your literature review might require several rounds of re-drafting and significant edits.
If you are usually a 'dive in without a plan and just get drafting' kind of writer, be prepared to modify your approach if you start to feel overwhelmed. Mind mapping, organising your ideas on a marker board, or creating a bullet-pointed reverse outline can help if you start to feel lost.
Alternately, if you are usually a 'create a strict, detailed outline and stick to it at all costs' kind of writer, keep in mind that long-form writing often calls for writers to modify their plans for content and structure as their work progresses and evolves. It can help such writers to schedule periodic 'audits' of their outlines, with the aim being to assess what is still working and what else needs to be added, deleted or modified.
Here’s a final checklist for writing your literature review. Remember that not all of these points will be relevant for your literature review, so make sure you cover whatever’s appropriate for your dissertation. The asterisk (*) indicates any content that might not be relevant for your dissertation. You can save your own copy of the checklist to edit using the Word document, below.
| Aspect of Literature Review | Yes/Unsure/No |
|---|---|
| I have searched for and critically evaluated a wide range of literature related to my topic. | |
| I have verified that my sources are of an appropriate standard and nature for my discipline. | |
| I have considered both the factual or topical themes and the theoretical framework(s) relevant to my research question.* | |
| I have synthesized sources throughout my review rather than discussing sources as isolated 'islands'. If I do focus on a source in isolation, I have done so for strategic and intentional reasons. | |
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I have structured my literature review in a manner that moves from the broad to the narrow. |
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| I have used heading and subheading hierarchies and formatting that align with the expectations of my school or style guide. | |
| I have used my literature review to provide meaningful context, ultimately identifying the research gap(s) to which my own work responds. |
