Systematic Review vs Literature Review: Complete Guide for UK Dissertations
You are writing your methodology chapter. Your supervisor has told you to conduct a "review of the literature." But the marking rubric mentions systematic reviews. Your module handbook uses both terms interchangeably. Now you are not entirely sure which one you are actually supposed to do — and the deadline is closer than you would like.
This confusion is more common than you might think. Both methods involve reviewing academic sources, and both appear in dissertations across UK universities. But they operate on completely different academic logic. Choosing the wrong one does not just cost you marks — it can undermine the entire credibility of your research design.
This guide explains exactly what each review type is, how they differ, when to use each one, and — critically — how to make the right choice for your specific research question. Real examples are included throughout.
Quick Answer A literature review is a flexible, interpretive overview of existing research on a topic. It suits essays, dissertations, and theoretical studies. A systematic review follows a strict, pre-registered protocol designed to minimise bias and produce reproducible findings. It suits empirical research, health sciences, and evidence-based policy work. The two are not interchangeable. |
At a Glance: Systematic Review vs Literature Review
| Feature | Literature Review | Systematic Review |
|---|---|---|
| Purpose | Explore a topic broadly | Answer a specific research question |
| Structure | Flexible / thematic / narrative | Fixed protocol (PRISMA) |
| Search Strategy | Selective, researcher-led | Comprehensive, predefined keywords |
| Source Types | Journals, books, reports, theory | Empirical studies meeting set criteria |
| Bias Level | Higher (subjective) | Lower (protocol-controlled) |
| Reproducibility | Low | High |
| Time Required | Weeks to a few months | 6–18 months (often longer) |
| Common In | Humanities, social sciences, most UG/PG dissertations | Healthcare, psychology, policy, PhD research |
Why Choosing the Right Review Type Determines Your Dissertation Grade
Choosing an appropriate review type is not a minor technical decision. It has a direct impact on your research quality, your methodology chapter mark, and your academic credibility. UK university marking schemes assess methodological alignment — whether the method you chose actually fits the question you are asking.
A mismatch creates immediate red flags for markers. Using a narrative literature review for a question that demands structured evidence synthesis reduces reliability. Applying a systematic review methodology to a broad theoretical discussion adds unnecessary rigidity and often produces weaker conceptual argument. Both scenarios cost marks.
Key Reasons This Choice Matters
- Academic credibility: Proper alignment increases trust in your findings
- Assessment performance: Methodology is heavily weighted in dissertation marking rubrics
- Research clarity: A clear method prevents confusion in your analysis and write-up
- Bias control: Systematic approaches reduce subjective interpretation of evidence
- Time efficiency: Choosing correctly prevents significant rework at the final stage
- Supervisor approval: A well-chosen method improves your proposal acceptance rate
Types of Literature Review: Narrative, Scoping, Integrative & Systematic
The term "literature review" is often used as a catch-all, but it actually describes a family of related methods. Understanding which type is being discussed — or required — is the first step to making the right decision.
Narrative Review
Definition: A broad, flexible overview of existing literature on a subject that does not follow a fixed search procedure.
A narrative review is a broad and flexible overview of the existing literature on a subject. It does not follow a fixed search procedure, which means that the researcher can choose and interpret studies more freely. Generally, this type is used to build background knowledge and to explain general concepts. As it is subjective in selecting the sources, it is not suitable to show highly conclusive or evidence-based results. It is the most common type used in undergraduate and postgraduate dissertations across humanities and social sciences.
Scoping Review
Definition: A review conducted to identify concepts, evidence gaps, and patterns in literature on a developing or poorly defined topic.
A scoping review maps what research exists before narrowing down a specific focus. It is quite different in structure from a narrative review but is not intended to be synthesising or concluding. It is particularly beneficial when the topic is developing or not clearly defined so that the researcher can get a big picture of the evidence before narrowing down a research focus.
Integrative Review
Definition: A review that synthesises results from multiple types of research — qualitative, quantitative, and theoretical — to provide a comprehensive overview.
An integrative review synthesises results from various kinds of research, including qualitative research, quantitative data and theoretical studies. It gives a more comprehensive overview of a topic by integrating various viewpoints. Although it is more structured than a narrative review, it does not require the same level of strict protocol or exhaustive searching as a systematic review. It is widely applied in sectors such as education and health care, where there are multiple evidence requirements for this.
Systematic Review
Definition: A review that uses a clearly defined, pre-registered methodology for collecting and analysing all relevant studies on a research question, following PRISMA guidelines.
A systematic review uses a clearly defined and highly structured methodology for the process of collecting and analysing all relevant studies for a research question. It has well-defined inclusion/exclusion criteria and is designed to minimise bias and produce reliable, reproducible findings. May include meta-analysis if studies allow statistical pooling.
What Is a Literature Review? Definition, Structure & Academic Purpose
Definition: A literature review is a structured academic discussion of existing research on a specific topic. It interprets, compares, and critically analyses previous studies to identify what is known, what is debated, and what remains unexplored — without following a fixed search protocol. |
According to the University of Liverpool Library, systematic reviews use transparent and reproducible methods defined before the search begins, while literature reviews are less rigorous and mainly used to provide background or contextual understanding of a topic.
The structure and format of the literature review depend on the research topic, and it can be organised in a thematic or chronological way. It can also be organised by research design — separating qualitative and quantitative work. This flexibility is one of its strengths for theoretical and humanities-based research.
Core Components of a Literature Review
- Introduction section: Defines topic scope and objectives
- Thematic discussion: Groups similar ideas from different studies
- Critical analysis: Evaluates strengths and weaknesses of research
- Research gaps: Identifies missing or underexplored areas
- Conclusion section: Summarises findings and transitions to research aim
Purpose of a Literature Review
- To understand existing knowledge in a field
- To identify research gaps for new studies
- To support theoretical framework development
- To compare different academic perspectives and schools of thought
Literature Review Example (Undergraduate Dissertation)
Example Research Question "How have sociological theories of identity evolved in response to social media between 2010 and 2024?" This question is exploratory and theoretical. It calls for a narrative literature review, not a systematic one. The student would thematically organise sources around key theorists (Goffman, Bauman, boyd), trace how arguments have developed, and identify gaps where social media has not yet been fully addressed. No predefined search protocol is needed. |
What Is a Systematic Review? Definition, Protocol & When to Use It
Definition: A systematic review is a research methodology that uses a pre-registered, transparent protocol to identify, screen, and synthesise all relevant empirical studies addressing a specific research question — designed to minimise bias and ensure reproducibility. |
Unlike traditional reviews, systematic reviews do not choose the studies as a subjective process. Rather, every decision — from which databases to search, to which keywords to use, to which studies to include or exclude — is made before the search begins and documented in a protocol. Many UK researchers register their protocol on PROSPERO (the international register of systematic reviews) before beginning work.
Researchers use systematic reviews when they need strong, evidence-based conclusions. This is particularly prevalent in areas of healthcare, psychology and policy research. They are increasingly expected at PhD level, though some taught master's programmes now include them in methodology training.
Purpose of a Systematic Review
- To answer a clearly defined research question
- To collect all relevant empirical evidence
- To minimise bias in study selection
- To ensure reproducibility of findings
- To support evidence-based decision-making in policy and clinical practice
Systematic Review Example (Health Sciences Research)
Example Research Question "Does cognitive behavioural therapy (CBT) reduce symptoms of generalised anxiety disorder in adults aged 18–65, compared to pharmacological treatment?" This is a specific, answerable question with a measurable outcome. It calls for a systematic review. The researcher would register a PICO-framed protocol on PROSPERO, search PubMed, PsycINFO, and Cochrane using Boolean operators (e.g., "cognitive behavioural therapy" AND "generalised anxiety" AND "randomised controlled trial"), apply PRISMA screening guidelines, and produce a CASP-assessed synthesis of findings. |
PRISMA Guidelines: The Reporting Framework Behind Every Systematic Review
PRISMA — Preferred Reporting Items for Systematic Reviews and Meta-Analyses — is the internationally recognised reporting standard for systematic reviews. First published in 2009 and updated in 2020, PRISMA does not change the research, but it does help to make sure that all aspects of the research are recorded. For UK students and researchers, following PRISMA is not optional in systematic review work; it is expected by supervisors, journals, and ethics boards.
What PRISMA Requires: Step-by-Step
- Step 1 — Define the research question: Use the PICO framework (Population, Intervention, Comparison, Outcome) to frame a specific, answerable question
- Step 2 — Register your protocol: Submit your pre-defined methodology to PROSPERO before searching begins
- Step 3 — Identify search databases: Select relevant databases (PubMed, Scopus, Web of Science, PsycINFO, Cochrane Library) and define Boolean search strings
- Step 4 — Screen titles and abstracts: Apply inclusion and exclusion criteria to all retrieved records — independently if possible, with a second reviewer to reduce bias
- Step 5 — Full-text assessment: Retrieve and assess full texts of studies that passed screening
- Step 6 — Quality appraisal: Use a tool such as the CASP (Critical Appraisal Skills Programme) checklist to assess methodological quality
- Step 7 — Synthesise findings: Produce a narrative synthesis, or a meta-analysis if studies allow statistical pooling
- Step 8 — Report using the PRISMA flow diagram: Complete the four-stage flow diagram showing records identified, screened, assessed, and included
The PRISMA 2020 statement is available in full on the official PRISMA website. The Cochrane Collaboration publishes the gold standard for systematic reviews in health research and is widely cited in UK universities.
Key Functions of PRISMA
- Ensures structured reporting of review process
- Improves transparency in study selection
- Provides flow diagrams for screening process
- Standardises reporting across academic fields
How Data Is Collected and Analysed in Each Review Type
The biggest difference between review methods is likely to be in data collection and analysis. For students in the methodology planning stage, this distinction determines the scale, timeline, and complexity of the review work involved.
Data Collection in a Literature Review
Literature reviews typically involve the gathering of studies that are relevant to the topic. Journal articles, books, reports and conference papers are among the kinds of sources that can be searched. The process is somewhat flexible. Researchers then analyse findings by identifying themes, arguments, theoretical debates, and patterns across studies.
Data Collection in a Systematic Review
Researchers develop a comprehensive search protocol based on predetermined keywords and academic databases, like PubMed, Scopus, Web of Science, or PsycINFO. All steps are recorded in detail. Every step is logged so the entire process can be audited and replicated. Grey literature — unpublished studies, government reports, conference abstracts, and theses — is also considered to reduce publication bias. Analysis involves structured evidence synthesis, often using the CASP checklist.
| Aspect | Literature Review | Systematic Review |
|---|---|---|
| Search Strategy | Flexible and selective | Structured and protocol-based |
| Study Selection | Researcher judgment | Defined criteria |
| Data Type | Theoretical + qualitative | Empirical evidence |
| Analysis Method | Thematic interpretation | Evidence synthesis |
| Bias Level | Higher | Lower |
| Grey Literature | Optional / informal | Actively sought to reduce publication bias |
Systematic Review vs Meta-Analysis: Are They the Same Thing?
Systematic reviews and meta-analyses are not synonymous, as students sometimes think. A systematic review is the full research process — defining a question, searching databases, screening studies, appraising quality, and synthesising findings. A meta-analysis is a statistical technique used to numerically combine the results of multiple studies — it is a tool that can be used within a systematic review, not a synonym for it.
A systematic review can contain a meta-analysis, but only when the included studies are sufficiently similar in design, population, and outcome measurement to allow meaningful statistical pooling. Not all systematic reviews include a meta-analysis, and a meta-analysis cannot exist without the systematic review process that generates the studies being combined.
Relationship Between the Two
- Systematic review = collection + evaluation
- Meta-analysis = statistical combination
- Can exist together in quantitative research
- Not required in all systematic reviews
7 Key Differences Between Literature Review and Systematic Review
The difference between a literature review and a systematic review is not just about structure. The difference is in purpose, depth and methodological control. Understanding these differences gives you the framework to make the right methodological choice and defend it in your dissertation.
1. Purpose and Research Goal
- Literature review: A literature review is used to explore a topic broadly and build general understanding. It supports researchers talking about ideas, theories and patterns from the work that has already been done.
- Systematic review: Systematic review, on the contrary, is conducted to address a very precise research question. It emphasises gathering all the relevant information and analysing it systematically.
2. Structure and Format
- Literature review: There is no set structure to writing a literature review. It can be arranged thematically, chronologically or conceptually, depending on the topic.
- Systematic review: The systematic review is structured and set out in a predetermined way. Every stage, from search to reporting, is documented.
| Literature Review | Systematic Review |
|---|---|
| Flexible structure | Fixed methodology |
| Thematic or narrative flow | Step-by-step protocol |
| No strict rules | PRISMA-based reporting |
| Scope defined by researcher | Scope pre-registered (e.g., PROSPERO) |
3. Search Strategy
- Literature review: A selective search strategy is used in the literature review. Studies are selected according to relevance, availability, and the academic judgement of the researchers.
- Systematic review: Systematic reviews use a predefined and transparent search strategy. Databases are preselected, the keywords are thoughtfully composed using Boolean operators, and all search steps are documented.
4. Sources and Selection Criteria
- Literature review: Literature Review involves a variety of literature, including journal articles, books, reports, and theoretical papers.
- Systematic review: A systematic review only considers those studies that fulfil predefined inclusion and exclusion criteria. These criteria can include study design, population, time interval or methodological quality.
| Aspect | Literature Review | Systematic Review |
|---|---|---|
| Source Range | Broad | Restricted |
| Selection Method | Subjective judgment | Defined criteria |
| Focus | Conceptual relevance | Evidence validity |
5. Reproducibility and Transparency
- Literature review: The problem with literature reviews is their difficulty in being reproduced; they will vary from person to person, depending on how the researcher interprets the studies.
- Systematic review: The goal of systematic reviews is to be reproducible. All steps are documented, including search criteria, databases, etc. This makes the process transparent and enables other researchers to repeat the study with similar results.
6. Time, Resources, and Effort
- Literature review: Literature reviews typically are shorter because they need not be performed under strict protocols or an exhaustive search. These can be completed in weeks to a few months at postgraduate level.
- Systematic review: Systematic reviews are time-consuming and resource-intensive. They take 6–18 months as a minimum at research level — often longer. At PhD or funded research level, the process typically involves a team.
7. When to Use Each Type
A literature review is most appropriate for an exploration of a topic, for the development of a theoretical background or for the discussion of several viewpoints. It is usually employed in essays, dissertations and introduction research papers.
When the research demands appropriate evidence-based conclusions, a systematic review is used. It is often used in healthcare, policy studies, and scientific disciplines that require a high level of accuracy and replication.
| Use a Literature Review when... | Use a Systematic Review when... |
|---|---|
| Your question is exploratory or theoretical | Your question is specific and empirically answerable |
| You are writing a dissertation in humanities, law, or social sciences | You are working in health, psychology, education, or policy research |
| You need to build a conceptual or theoretical framework | You need to synthesise evidence for a clinical or policy decision |
| You are at undergraduate or taught master's level | You are conducting doctoral or funded research |
| Your supervisor has not specified a protocol-based method | Your methodology chapter requires PRISMA compliance |
Pro Tip: If you want to go a step further and understand how research ideas are structured, check our guide on How to Write a Dissertation in One Week to understand how to complete your dissertation in minimum time without losing quality. |
Which Review Type Is Right for Your Research? Final Decision Guide
If you are still uncertain after reading this guide, work through these three questions in order:
- How specific is your research question? If it can be framed using the PICO structure (Population, Intervention, Comparison, Outcome), a systematic review may be appropriate. If it is broader and conceptual, a literature review is the right choice.
- What does your subject discipline expect? Health sciences, clinical psychology, and evidence-based policy typically require systematic reviews. Humanities, law, education, business, and social sciences typically expect literature reviews at dissertation level.
- What does your supervisor or marking rubric specify? When in doubt, ask your supervisor directly. The marking rubric will often specify whether a "review of the literature" means a narrative review or a systematic one. Do not assume.
Conclusion: Two Different Tools for Two Different Research Purposes
A literature review and a systematic review are not competing methods — they are complementary tools designed for fundamentally different research purposes. A literature review offers flexibility and interpretive depth, and a systematic review offers structured and evidence-based results.
For most UK undergraduate and postgraduate dissertation students, a well-executed literature review is both appropriate and expected. For doctoral researchers and those working in empirical disciplines, systematic reviews set the methodological standard.
Both methods have their place but are quite separate in purpose. The key is alignment: choose the method that fits the question you are asking, document your choice clearly in your methodology chapter, and execute it with rigour. Doing so will strengthen every other part of your dissertation.
Frequently Asked Questions
When Should Researchers Use a Systematic Review?
A systematic review should be used by the researcher to identify, assess and combine the best available evidence from multiple studies to make decisions based on evidence or set policies. It reduces bias, resolves conflicting findings, and prevents duplication of research. It is also required when the research must be transparent, reproducible, and bias-controlled — typically at doctoral level or in funded research.
What Are the Advantages of a Literature Review?
Literature review provides a summary of the current research and highlights existing theories, experts and gaps. It prevents duplication, creates a sound theoretical foundation and enhances the credibility and method of research. It is flexible, faster to complete, and better suited to theoretical, exploratory, or conceptual research questions.
How Long Does a Systematic Review Take to Complete?
The duration of a systematic review is typically 6-18 months, with the time often being about a year or more. The timeline spans protocol development, database searching, dual screening, quality appraisal, and synthesis — each a substantial phase in its own right.
Can a Literature Review Be Used as Part of a Systematic Review?
No — a literature review and a systematic review are distinct methodologies, not nested components. However, some researchers begin with a scoping or narrative review to map the field before conducting a more structured systematic review.
What Is the Difference Between a Scoping Review and a Systematic Review?
A scoping review maps the existing evidence on a topic to identify gaps and patterns — it does not synthesise conclusions or apply quality appraisal. A systematic review answers a specific research question through comprehensive, protocol-governed evidence synthesis. Scoping reviews are exploratory; systematic reviews are conclusive.
How Many Studies Do You Need for a Systematic Review?
There is no fixed minimum. The number of included studies depends on what exists in the literature that meets your inclusion criteria. A systematic review with five high-quality RCTs can be more credible than one with 40 low-quality observational studies. Methodological rigour, not volume, determines the quality of the review.
Can I Do a Systematic Review for My Dissertation?
Yes — but it depends on your level of study, subject discipline, and supervisor guidance. Some master's programmes require a systematic review in specific disciplines such as health sciences or evidence-based education. Most undergraduate and taught postgraduate dissertations use a literature review. Always confirm the expected approach with your supervisor before beginning.
What Are the Main Types of Literature Reviews?
Narrative, systematic, scoping and meta-analysis are the four major kinds of literature review. Narrative reviews provide a broad overview without a fixed protocol; systematic reviews use a rigorous, protocol-governed approach; scoping reviews summarise the current state of the literature on a developing topic; and meta-analyses statistically combine the outcomes of studies. Meta-analysis is a statistical technique that can be incorporated into a systematic review, not a standalone review type.
References:
- University of Liverpool. (2026). How do I deposit my thesis into the repository? LibAnswers. https://libanswers.liverpool.ac.uk/faq/260223
- PRISMA. (2026). The PRISMA statement for systematic reviews and meta-analyses. http://www.prisma-statement.org/
- Cochrane. (2026). Trusted evidence. Informed decisions. Better health. https://www.cochrane.org/
Cite this article
If you want to cite this source, you can copy and paste the citation or click the Cite this article button to automatically add the citation to our free Citation Generator.
Jonat N. (July 8, 2022).
Systematic Review vs Literature Review: Complete Guide for UK Dissertations to Improve Grades and Save Time Retrieved August 26, 2026, from
https://www.cheap-essay-writing.co.uk/blog/2022/07/systematic-review-vs-literature-review
WhatsApp Now