What Is PRISMA 2020? A Complete Guide to Systematic Literature Reviews for PhD Researchers
A systematic literature review requires a clear and transparent process for finding, selecting, evaluating and reporting relevant research studies. This is where PRISMA 2020 becomes important.
PRISMA stands for Preferred Reporting Items for Systematic Reviews and Meta-Analyses. It is a reporting guideline developed to help researchers clearly report how a systematic review was conducted and what was found.
PRISMA 2020 updated the earlier PRISMA 2009 statement. It includes a 27-item checklist, an expanded checklist, an abstract checklist and flow-diagram templates for systematic reviews.
For PhD scholars, understanding PRISMA can be particularly useful when a research project involves a systematic literature review, evidence synthesis or a review paper that requires transparent reporting.
But there is an important point to understand:
PRISMA is a reporting guideline. It is not, by itself, a research methodology.
In this guide, we explain what PRISMA 2020 means, when it is used, how the PRISMA flow diagram works and how it can be incorporated into a systematic literature review.
H2: What Does PRISMA Stand For?
PRISMA stands for:
Preferred Reporting Items for Systematic Reviews and Meta-Analyses
The guideline was developed to improve the transparency and completeness of reporting in systematic reviews.
A systematic review normally involves a defined research question, planned eligibility criteria, structured searching, study selection, assessment and synthesis of evidence.
PRISMA helps researchers report this process clearly, so readers can understand:
Why the review was conducted
What research question was addressed
Where studies were searched
How studies were selected
Which studies were excluded
How the included evidence was analysed or synthesised
What the review found
The PRISMA 2020 guideline is the current main PRISMA reporting guideline and replaces PRISMA 2009.
What Is PRISMA 2020?
PRISMA 2020 is the updated version of the PRISMA reporting guideline.
It provides researchers with structured reporting recommendations for systematic reviews. The guideline contains 27 main checklist items, with some items containing sub-items.
The main PRISMA 2020 resources include:
PRISMA 2020 checklist
Expanded PRISMA checklist
PRISMA 2020 flow diagram
PRISMA 2020 statement
PRISMA 2020 explanation and elaboration guidance
The official PRISMA website provides these resources for researchers and authors.
Therefore, when a PhD scholar says that their literature review needs to follow PRISMA, it is important to first understand what type of review they are conducting and what reporting requirements apply.
Is PRISMA a Research Methodology?
This is one of the most common questions about PRISMA.
No. PRISMA itself is not a research methodology.
PRISMA is primarily a reporting guideline.
It helps researchers report a systematic review in a transparent and structured manner. The actual systematic review involves decisions about the research question, eligibility criteria, information sources, search strategy, study selection, data collection, assessment and synthesis.
In simple words:
Systematic Review = The research/review process
PRISMA = A guideline for transparently reporting that process
This distinction is important when preparing a PhD thesis or research paper.
When Should PhD Researchers Use PRISMA?
PRISMA is particularly relevant when conducting and reporting a systematic review.
For example, a PhD researcher may want to systematically examine existing studies on:
Artificial intelligence applications in healthcare
Machine learning in medical diagnosis
Renewable energy technologies
Digital learning in higher education
Cybersecurity methods
Sustainable manufacturing
Healthcare interventions
Educational technologies
Instead of simply collecting papers and summarising them, a systematic review follows a structured process for identifying and selecting relevant evidence.
PRISMA can then help the researcher report that process transparently.
However, not every literature review automatically requires PRISMA. The appropriate reporting guideline depends on the type and scope of the review. The PRISMA website also provides extensions for particular review types and evidence-synthesis approaches.
What Is the PRISMA 2020 Checklist?
The PRISMA 2020 checklist is one of the main components of the guideline.
It contains 27 items covering important aspects of reporting a systematic review. These include areas such as:
Title
Abstract
Rationale
Objectives
Eligibility criteria
Information sources
Search strategy
Study selection
Data collection
Risk of bias assessment
Synthesis methods
Results
Limitations
Conclusions
Registration and protocol information
The checklist helps researchers check whether important information about the systematic review has been reported.
Researchers can use the checklist while preparing their manuscript rather than waiting until the end.
This can make it easier to identify missing information before submitting a systematic review paper.
What Is a PRISMA Flow Diagram?
The PRISMA flow diagram is one of the most recognisable parts of a PRISMA-based systematic review.
It visually presents how records move through the different stages of the review.
The diagram generally shows:
Identification → Screening → Eligibility → Included
It records information such as:
Number of records identified
Number of duplicate records removed
Number of records screened
Number of records excluded
Number of full-text reports assessed
Reasons for exclusions
Number of studies finally included
The official PRISMA 2020 flow diagram templates are designed to show the flow of information through the different phases of a systematic review. Different templates are available depending on the sources searched and whether the review is new or updated.
How Does the PRISMA Flow Diagram Work?
A simplified PRISMA review process can be understood through four major stages.
1. Identification
Researchers search relevant databases and other information sources using a predefined search strategy.
The number of records identified is documented.
2. Screening
Duplicate records are removed, and the remaining records are screened based on their titles and abstracts.
Records that clearly do not meet the review criteria are excluded.
3. Eligibility
Potentially relevant studies are examined in greater detail, often through full-text assessment.
Studies that do not meet the predefined eligibility criteria are excluded, with reasons documented.
4. Included
The studies that satisfy the eligibility criteria are included in the systematic review.
The final number of included studies is reported.
This process creates a transparent record of how the researcher moved from a large set of search results to the final evidence base.
How to Conduct a Systematic Literature Review Using PRISMA
PRISMA does not replace the actual systematic review process. Instead, the review should be carefully planned and then reported according to the relevant PRISMA recommendations.
A typical process may involve the following steps:
Step 1: Define the Research Question
Begin with a clearly defined research question or objective.
A focused question helps determine what type of literature needs to be searched and which studies are relevant.
Step 2: Define Inclusion and Exclusion Criteria
Specify the criteria that determine which studies will be considered.
For example, criteria may relate to:
Publication period
Research area
Population or context
Study design
Language
Research outcomes
These criteria should be established appropriately for the review question.
Step 3: Identify Information Sources
Select suitable databases and other sources for identifying relevant research.
The PRISMA 2020 checklist asks researchers to report the information sources used and the dates on which they were last searched.
Step 4: Develop the Search Strategy
Create appropriate search terms and combinations based on the research question.
The search strategy should be documented clearly enough for readers to understand how relevant studies were identified.
Step 5: Screen the Retrieved Studies
Remove duplicates and screen the identified records according to the predefined criteria.
Titles and abstracts are commonly screened first, followed by full-text assessment where appropriate.
Step 6: Assess the Eligible Studies
The potentially relevant studies are assessed against the eligibility criteria.
Depending on the review, researchers may also assess risk of bias or methodological quality using an appropriate approach.
Step 7: Extract and Synthesize the Findings
Relevant information is extracted from the included studies.
The findings are then organised and synthesised according to the research question and the planned review approach.
Step 8: Report the Review Using PRISMA
Finally, the systematic review is reported transparently using the relevant PRISMA 2020 checklist items and flow diagram.
PRISMA Checklist vs PRISMA Flow Diagram
Although both are part of PRISMA 2020, they serve different purposes.
PRISMA Component | Main Purpose |
PRISMA Checklist | Helps report the important components of the systematic review |
PRISMA Flow Diagram | Shows how records moved through identification, screening, eligibility and inclusion |
Expanded Checklist | Provides additional reporting detail for the checklist items |
Abstract Checklist | Provides reporting guidance specifically for systematic review abstracts |
The official PRISMA resources provide both the checklist and flow-diagram templates.
Therefore, a researcher should not think of the PRISMA flowchart as the entire PRISMA process. The flow diagram is only one component of the broader reporting guideline.
PRISMA vs Traditional Literature Review
A traditional or narrative literature review and a systematic review are not necessarily conducted in the same way.
A narrative literature review may focus on discussing and synthesising important concepts, theories, findings and research gaps within a particular research area.
A systematic review generally follows a more explicitly planned and documented process for searching, selecting and synthesising evidence.
PRISMA is especially relevant when reporting a systematic review.
For a PhD scholar, the first question should therefore be:
“What type of literature review am I conducting?”
Only after establishing this should the appropriate review approach and reporting guideline be selected.
Common Mistakes When Using PRISMA
PhD researchers sometimes make mistakes when trying to incorporate PRISMA into their review.
Some common problems include:
1. Treating PRISMA as a Research Methodology
PRISMA is primarily a reporting guideline, not a standalone research methodology.
2. Creating a Flow Diagram Without Maintaining Search Records
The numbers shown in the flow diagram should come from the actual search and screening process.
3. Using Incorrect Numbers
The number of records identified, screened, excluded and included should be consistent throughout the review.
4. Not Reporting Reasons for Exclusion
Where applicable, the reasons for excluding full-text reports should be documented and reported appropriately.
5. Using PRISMA for Every Literature Review
PRISMA is not automatically required simply because a thesis contains a literature review. Its relevance depends on the review type and reporting requirements.
6. Focusing Only on the Flowchart
A PRISMA flow diagram alone does not make a systematic review compliant with PRISMA 2020. The broader checklist and reporting recommendations also need to be considered.
How PRISMA Can Support a PhD Literature Review
For a PhD scholar conducting a systematic literature review, PRISMA can help create a more transparent structure for reporting the literature-search and study-selection process.
However, developing a strong literature review involves much more than preparing a PRISMA flow diagram.
The chapter may also require:
Critical analysis of existing studies
Comparison of research findings
Thematic organisation
Identification of limitations
Synthesis of existing knowledge
Identification of research gaps
Connection between previous research and the current study
Clear academic structure and argument development
If you need support developing your literature review chapter, you can explore PhD Literature Review Chapter Development Services offered by PATN Research.
The support can be relevant to scholars who need assistance with structured literature review development, critical analysis, synthesis, research-gap identification and systematic-review/PRISMA-related requirements.
Frequently Asked Questions About PRISMA
1.What is PRISMA in research?
PRISMA stands for Preferred Reporting Items for Systematic Reviews and Meta-Analyses. It is a reporting guideline that helps researchers transparently report systematic reviews.
2.What is PRISMA 2020?
PRISMA 2020 is the updated PRISMA reporting guideline. It includes a 27-item checklist, an expanded checklist, an abstract checklist and flow-diagram templates.
3. Is PRISMA a methodology?
No. PRISMA is primarily a reporting guideline. It supports transparent reporting of systematic reviews rather than functioning as a standalone research methodology.
4.What is a PRISMA flow diagram?
A PRISMA flow diagram visually presents the movement of records through the stages of a systematic review, including identification, screening, eligibility and inclusion.
5.How many items are in the PRISMA 2020 checklist?
The PRISMA 2020 checklist contains 27 main items, with some items containing sub-items.
6.Is PRISMA required for every PhD literature review?
No. PRISMA is particularly relevant to systematic reviews and should not automatically be applied to every type of literature review.
7. Can PRISMA be used for a PhD thesis?
Yes, when the research includes a systematic review for which PRISMA is an appropriate reporting guideline. The exact requirements depend on the review type, research question and institutional or publication requirements.
Complete Conclusion
PRISMA 2020 has become an important reporting guideline for researchers conducting and reporting systematic reviews. It provides a structured way to communicate how a review was planned and reported, including the information sources, search strategy, study selection, synthesis and results.
The PRISMA checklist helps researchers address important reporting requirements, while the PRISMA flow diagram provides a visual representation of how records move from identification through screening and eligibility to the final included studies.
For PhD researchers, the most important point is to understand that PRISMA is not simply a flowchart and it is not a standalone research methodology. It is a reporting guideline that should be used appropriately according to the type of systematic review being conducted.
A well-developed systematic literature review therefore requires more than preparing a PRISMA diagram. It requires a clearly defined research question, appropriate search strategy, suitable inclusion and exclusion criteria, systematic study selection, meaningful synthesis of findings and a clear connection between the existing literature and the research problem.
When these elements are properly integrated, the literature review can provide a stronger and more transparent foundation for the overall research study.
Need Support With Your Literature Review?
Developing a systematic literature review or incorporating PRISMA requirements into a PhD thesis can involve several stages, from literature searching and study selection to critical analysis, synthesis and research-gap identification.
If you need assistance with your literature review chapter, explore PhD Literature Review Chapter Development Services at PATN Research.
Get support for your literature review development based on your research requirements.
Comments