Structuring a literature review
In general, literature reviews are structured in a similar way to a standard essay, with an introduction, a body and a conclusion. These are key structural elements. Additionally, a stand-alone extended literature review has an abstract. Throughout, headings and subheadings are used to divide up the literature review into meaningful sections.
There is no single “correct” structure for how to structure the content of your literature review – every review is shaped by the nature of the field being reviewed and the specific argument the review is supporting. Here are some common literature review organising patterns:
- historical development (chronological)
- pros and cons
- methodological issues
- key works of a single author
- key works in a particular field of study
For example, a literature review on the definitions of key terms or concepts in a particular field of study might analyse a variety of definitions and conclude by defending a selected definition.
Some of the organising patterns listed above may be used in combination.
If you are writing a stand-alone extended literature review, you are required to provide an abstract. The purpose of an abstract is to provide potential readers with an overview of the review content, so that they can determine if it is relevant to their research. The abstract should include brief background information, including any knowledge gaps or discrepancies that the review aims to address, as well as a statement regarding the purpose and scope of the review. A complete abstract also includes a brief statement of the main findings and how they relate to the broader context. The example abstract below includes these elements.
Munchausen Syndrome (MS) is a chronic psychological disorder where sufferers intentionally fabricate illness or injury with the purpose of assuming the sick patient role. There are many serious consequences of the actions by MS sufferers and therefore early diagnosis is crucial. MS, however, is an inherently complex disorder and there are no established means of diagnosis.
These sentences provide brief background information, including the gaps in the literature that the review aims to address.
This review examines the use of a multidisciplinary approach for the diagnosis of MS which requires the cooperation of the primary physician, the laboratory and a psychiatrist.
This sentence describes the purpose and scope of the review. Providing specific information as to what your review covers helps your readers determine whether your review is useful for their research.
The findings of this review indicate that each of these parties have an essential and unique role to play in overcoming the diagnostic challenges of MS and this supports the use of a multidisciplinary approach. Additionally, this is only achieved through open communication and information sharing between these different healthcare professionals.
These sentences summarise the main findings and how they relate to the broader context.
Not all introductions follow exactly the same order. However, there are some key points to include in the introduction to provide your reader with the context and purpose of your review. The general guidelines for the structure of a literature review introduction are:
- Start with a broad introduction to the topic. Include relevant background information and definitions or explanations of the main terms and concepts.
- Provide information that is relevant for your specific topic, and explain the importance of your topic (e.g. why it’s worth reading your literature review).
- Tell the reader what the scope of your review is (e.g. what key points you will include in the body of your review).
- Tell your reader what the aim or purpose of your review is. This is often included at the end of the introduction.
The concentration of atmospheric carbon dioxide (CO2) has been increasing throughout recent history. It was steady at 280ppm until the industrial revolution (Wrobelwitz et al. 2013), after which it began rising, reaching just over 400ppm currently (Block et al. 2017). This change in concentration of CO2 is predicted to significantly impact the global environment (Fang et al. 2017). Both precipitation levels and mean temperatures are expected to change as a result of such increases (Fang et al. 2017) which, coupled with the expectation of a growing population (Challinor et al. 2014), could heavily burden the ability of the global agricultural infrastructure to provide.
These sentences introduce the topic broadly, include relevant background information and explain key concepts.
These abiotic challenges are expected to impact growth speed, quality and yield of staple crops like wheat (Wroblewitz et al. 2013). Wheat is a source of food for over 90% of the global population (Cai et al. 2016) and provides 4.5 billion people with their necessary daily protein (Dubey et al. 2014). The importance this crop holds for the global population establishes the necessity for it to be able to thrive in a future climate.
These sentences provide key information that is relevant to the specific topic and explain the importance of the topic.
Therefore, this review aims to directly assess how global wheat crops will react to a rise in environmental CO2 and guide research of mitigation of any challenges wheat may face.
This sentence states the aim (or purpose) of the literature review. Notice that the specific aim is provided after general background and relevance to the topic, close to the end of the introduction.
Firstly, crop growth will be explored, then crop yield and finally yield quality within an environment of elevated CO2.
The sentence outlines the scope - the key points that will be discussed in the body of the review.
The body of the review contains your review of the literature relevant to your research question or aim. You should structure the body of your literature review in a logical and coherent way. Consider what your sub-topics or sections will be in order to answer your research question thoroughly and coherently. Then consider the most logical order to discuss your sections. Creating sub-headings for the sections of your review will assist you in creating a logical structure and keep you focused on sub-topics relevant to your research aim.
In the body of your literature review, it is important to analyse the literature rather than to merely describe the findings of a number of different literature sources. Some description of the key findings is important to give the reader context. However, your review should also include an analysis of the key themes, gaps in understanding, and points of disagreement between the different literature sources.
There are numerous ways to organise your body paragraphs, depending on your topic. You may want to organise some of your paragraphs:
- in chronological order, e.g. historical findings, more recent findings, current research
- group your literature sources into paragraphs based on similar arguments or findings
- categorise your sources into similar sub-topics and compare different findings within a single paragraph.
Remember to include accurate and relevant citations and references throughout this section.
The assignment excerpt below is an example of how to group similar findings together.
Body paragraph example 1
Multiple studies have found evidence supporting an increase in crop growth in an environment of elevated CO2. In their research, Cai et al. (2016) attributed this to enhanced leaf photosynthesis in C3 species like wheat when exposed to such an increase in the concentration of CO2 in the ambient air. In addition, Hӧgy and Frangmeier (2008) observed an acceleration of wheat growth ‘productivity’ under CO2 enrichment, the amplification of these processes ultimately leading to enhanced crop growth. Wang et al. (2016) supported these studies, completing a research project of wheat growth under elevated atmospheres of CO2 concentrations up to 500ppm. Comparing wheat crop growth under elevated CO2 conditions with those in ambient conditions, Wang et al. (2016) were able to significantly demonstrate that increases in atmospheric carbon could improve grain growth up to 8%.
This paragraph describes similar findings from multiple literature sources. Note the language used to highlight the fact that these are all similar findings, including “multiple studies”, “in addition” and “supported these studies”.
However, with CO2 elevation comes a myriad of other abiotic factors, including a rise in average temperature (Dahal et al., 2014). During an experiment of wheat growth in CO2 rich atmospheres by Hӧgy et al. (2009) the plants experienced a growing season with a mean temperature 1.8℃ higher than in previous years. Concurrently the crop experiences a shorter growth period, finishing their growth cycle earlier than normal. The rise in temperature, while hastening growth time, had a negative effect on crop yield and quality, suggesting that while elevated CO2 may increase growth processes, accompanying abiotic influences such as temperature increases may be detrimental to crop growth. Asseng et. al. (2013) supported this, contending that their predictive models indicate negative overall impacts on wheat crops at higher levels of warming as a result of CO2 increases.
The use of the word “however” indicates to the reader that this paragraph presents contrasting findings to the previous paragraph. In this case, the first paragraph discussed findings of increased wheat growth in the presence of increased CO2. The second paragraph discusses multiple findings that show negative effects on wheat quality at higher temperatures, which are associated with increased CO2.
Another method of organising your body paragraphs is to group papers together that have found different or contradictory results related to the same topic. This helps you to demonstrate your understanding of the literature and highlights the inconsistencies between findings. The assignment body paragraph below is an example of how this can be done.
Body paragraph example 2
In order to carry out self-regulation, patients must be able and encouraged to exert their autonomy, and be supported in such a way that they develop internalised motivations to do so, as suggested by SDT. Gourlan et. al. (2014) support this, demonstrating that amongst obese adolescents, incidence of physical activity was increased when individuals experienced a supervised exercise session that supported their autonomous needs. Patients were assumed to have performed such self-regulation due to the intrinsic origin of motivation to complete such tasks (Gourlan et al., 2014). However, not all literature supports this conclusion. Sripada et al. (2016) presents contrary evidence, demonstrating that no aspects of SDT needs (i.e. autonomy, competence, relatedness and intrinsic motivation) are related to treatment adherence, which requires an element of self-regulation.
This paragraph describes some discrepancy between different findings related to Self-Determination Theory needs (including motivation and autonomy) and the maintenance of healthy behaviours such as exercise and treatment adherence.
Conclude by demonstrating how you have answered your research question and/or how you have achieved your research aim. This tells the audience you have achieved what you intended. Then highlight the key points you discussed. Now you can refer to implications of this knowledge in a broader sense, as well as recommendations for future studies/research (if applicable). The conclusion starts specific and finishes broad.
There are several conventions to note when you are writing your conclusion:
- Don’t include new information in your conclusion. Instead, highlight the key points raised in the earlier sections of your literature review.
- Don’t include in-text citations in your conclusion. This relates to the point above in regards to not including new information.
The example below demonstrates the structural elements of a conclusion.
This review aimed to examine the emotional perception of self and others, and assessed the neurobiological underpinnings of Narcissistic Personality Disorder (NPD) in an attempt to improve understanding of the characteristics and development of the disorder. While findings are relatively inconsistent in regards to self-esteem in NPD, there is a definite influence of narcissistic traits (grandiosity, self-worth etc.) on the overall perception of self. Linking to impaired self-perception, NPD individuals also showed decreased ability to perceive and process the emotions of others. The presence of physical neural deficiencies provides a model which offers explanation for the previous two characteristics of NPD, as deficits in the prefrontal cortex have been linked to the impairment of emotional processing.
These sentences restate the research aim and demonstrate how the review has achieved the aim, as well as the key points that were discussed in the body.
It is proposed that future studies could further examine the role of the brain in reaction to various narcissistic traits, allowing for more specific identification of impaired neural structures as well as the development of intervention and treatment techniques. As positive emotion was found to be counter-transferrable and also beneficial to both therapists and NPD patients, developing therapies based around emotionally nourishing environments may decrease NPD traits and provide a stepping stone towards permanent treatment options.
These sentences provide recommendations for future studies and research based on the findings of this review.