PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews) is a 22-item reporting guideline specifically designed for scoping reviews. Published in 2018 by Tricco and colleagues, PRISMA-ScR provides a standardized framework for transparently reporting the methods and findings of scoping reviews, which differ from systematic reviews in purpose, scope, and methodology. Scoping reviews map the extent and nature of available evidence on a broad topic, whereas systematic reviews answer focused questions with rigorous quality assessment.
Understanding when and how to use PRISMA-ScR versus standard PRISMA 2020 is essential for researchers choosing between these evidence synthesis approaches and for ensuring correct reporting.
What Is a Scoping Review?
A scoping review is a type of evidence synthesis that aims to map the existing literature on a broad topic, identify key concepts, examine research gaps, and clarify definitions or conceptual boundaries. The foundational framework for scoping reviews was established by Arksey and O'Malley (2005) and refined by Levac, Colquhoun, and O'Brien (2010) and the Joanna Briggs Institute (JBI).
Scoping reviews differ from systematic reviews in several fundamental ways:
| Aspect | Scoping Review | Systematic Review |
|---|---|---|
| Purpose | Map available evidence | Answer a specific question |
| Research question | Broad, exploratory | Focused, answerable |
| Quality assessment | Optional (not required) | Required |
| Synthesis | Descriptive, tabular | Narrative or quantitative (meta-analysis) |
| Eligibility criteria | May evolve iteratively | Pre-specified and fixed |
| Reporting guideline | PRISMA-ScR | PRISMA 2020 |
For an in-depth comparison of systematic review and meta-analysis methodology, see our guide on meta-analysis vs systematic review.
The PRISMA-ScR 22-Item Checklist
PRISMA-ScR adapts the original PRISMA framework for the specific characteristics of scoping reviews. The 22 items are organized into five sections:
Title (Item 1)
Identify the report as a scoping review in the title. This distinguishes the methodology from systematic reviews and literature reviews.
Abstract (Item 2)
Provide a structured abstract including objectives, eligibility criteria, sources of evidence, charting methods, results, and conclusions. Use the term "scoping review" explicitly.
Introduction
Item 3: Rationale: Describe the rationale for the review, including what is known about the topic, why a scoping review (rather than a systematic review) is the appropriate approach, and what gap the review addresses.
Item 4: Objectives: State the objectives and research questions. Scoping review questions are typically broader than systematic review questions and may use the PCC (Population, Concept, Context) framework rather than PICO.
Methods
Item 5: Protocol and registration: Indicate whether a protocol exists, where it can be accessed, and registration details.
Item 6: Eligibility criteria: Specify inclusion and exclusion criteria. In scoping reviews, these may be refined iteratively as familiarity with the literature increases.
Item 7: Information sources: Describe all information sources searched (databases, registers, websites, experts, reference lists).
Item 8: Search: Present the full search strategy for at least one database, including limits and filters.
Item 9: Selection of sources of evidence: Describe the process for selecting sources (screening at title/abstract and full-text levels), number of reviewers, and conflict resolution.
Item 10: Data charting process: Describe the methods for extracting (charting) data, including forms used, piloting, and whether charting was done independently by two reviewers. Note: scoping reviews use "charting" rather than "extraction."
Item 11: Data items: List and define all variables for which data were charted.
Item 12: Critical appraisal: If performed, describe the methods used to assess the quality or risk of bias of included sources. Note: critical appraisal is optional in scoping reviews, which is a key difference from systematic reviews.
Results
Item 13: Selection of sources: Present the results of the search and selection process, ideally using a flow diagram.
Item 14: Characteristics of sources: Present the characteristics of included sources of evidence.
Item 15: Results of individual sources: Present the relevant results from each source.
Item 16: Synthesis of results: Present the main results of the charting and synthesis, typically in descriptive, tabular, or diagrammatic form.
Discussion
Item 17: Summary of evidence: Summarize the main findings in relation to the review objectives and research questions.
Item 18: Limitations: Discuss limitations of the scoping review and the evidence included.
Item 19: Conclusions: Provide a general interpretation of results, implications for practice and research, and recommendations for future systematic reviews on specific sub-questions identified.
Other
Items 20-22: Funding, conflicts of interest, and availability of data and materials.
Flow Diagrams for Scoping Reviews
PRISMA-ScR recommends using a flow diagram to document the study selection process, but the standard PRISMA 2020 flow diagram templates require adaptation for scoping reviews. Key differences include:
Terminology changes: Scoping reviews refer to "sources of evidence" rather than "studies," and "data charting" rather than "data extraction." The flow diagram labels should reflect this terminology.
No quality assessment filtering: Since critical appraisal is optional in scoping reviews, the flow diagram typically does not include a quality assessment exclusion stage unless the authors chose to conduct one.
Broader source types: Scoping reviews frequently include a wider range of source types (grey literature, policy documents, websites, guidelines) than systematic reviews, which may require additional documentation in the flow diagram.
You can adapt the four official PRISMA 2020 templates for scoping reviews using our free PRISMA flow diagram generator. Select the template that matches your sources (databases only or databases + other sources) and modify the terminology in your final report.
When to Choose a Scoping Review Over a Systematic Review
A scoping review is the appropriate methodology when:
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The topic is broad or emerging: You want to understand the extent and nature of available evidence before potentially conducting focused systematic reviews on specific sub-questions.
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You want to map key concepts: The primary aim is to identify and categorize concepts, definitions, or theoretical frameworks in a field.
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You need to identify research gaps: You want to determine where evidence is lacking to inform future primary research or focused systematic reviews.
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The evidence base is diverse: The available literature includes heterogeneous study designs, populations, and outcomes that would be difficult to synthesize quantitatively.
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Quality assessment is not the focus: Your goal is to describe what exists rather than to evaluate the strength of the evidence.
A systematic review is more appropriate when you have a focused, answerable question and need to assess the quality of evidence to inform practice or policy decisions. For a complete guide to the systematic review process, see our guide to conducting a systematic review from start to finish.
PRISMA-ScR vs PRISMA 2020: Key Differences
| Feature | PRISMA-ScR | PRISMA 2020 |
|---|---|---|
| Number of items | 22 | 27 |
| Quality assessment | Optional (Item 12) | Required |
| Meta-analysis reporting | Not applicable | Items for statistical synthesis |
| Certainty of evidence | Not required | GRADE or equivalent expected |
| Terminology | Sources of evidence, charting | Studies, data extraction |
| Flow diagram | Adapted from PRISMA | 4 official templates |
| Eligibility criteria | May evolve iteratively | Pre-specified and fixed |
| Protocol registration | Recommended (OSF, JBI) | Required (PROSPERO) |
Practical Examples
Example 1: Mapping a Broad Field
Question: "What is the extent and nature of published research on artificial intelligence applications in systematic review methodology?" PCC Framework: Population = systematic review researchers; Concept = AI applications; Context = systematic review methodology Approach: Scoping review appropriate because the field is broad, diverse study types expected, and the goal is to map what exists.
Example 2: Identifying Research Gaps
Question: "What is known about the use of patient-reported outcomes in clinical trials for rare diseases?" PCC Framework: Population = clinical trials in rare diseases; Concept = patient-reported outcomes; Context = clinical trial methodology Approach: Scoping review appropriate because the field is emerging, evidence is likely sparse and heterogeneous, and the goal is to identify gaps.
Common Mistakes in Scoping Review Reporting
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Using PRISMA 2020 instead of PRISMA-ScR: If your study is a scoping review, you should use PRISMA-ScR for reporting, not the standard PRISMA 2020 checklist.
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Labeling a literature review as a scoping review: A true scoping review requires systematic searching across multiple databases, explicit eligibility criteria, and a structured charting process. An informal narrative review of selected literature is not a scoping review.
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Conducting quality assessment when claiming it's unnecessary: If you include critical appraisal, document the methods. If you exclude it, justify why and acknowledge it as a limitation.
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Not using a flow diagram: While sometimes considered optional, a flow diagram significantly improves transparency and is expected by most journals.
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Drawing conclusions about effectiveness: Scoping reviews without quality assessment should not make claims about intervention effectiveness, as that requires a systematic review with quality assessment.
Frequently Asked Questions
Can I include a meta-analysis in a scoping review?
No. Meta-analysis is a statistical synthesis technique used in systematic reviews when studies are sufficiently homogeneous. Scoping reviews use descriptive synthesis (tables, charts, narrative summaries) because their broad scope typically produces too much heterogeneity for quantitative pooling.
Do I need to register a scoping review protocol?
Registration is recommended but not always required. PROSPERO does not currently accept scoping review registrations (only systematic reviews with health outcomes). Alternatives include the Open Science Framework (OSF), the JBI Scoping Review Registry, or publishing the protocol in a peer-reviewed journal.
What is the PCC framework for scoping reviews?
PCC stands for Population, Concept, Context, a framework for structuring scoping review questions. Unlike PICO (used for systematic reviews), PCC does not require a specific comparator or outcome, reflecting the broader, exploratory nature of scoping reviews.
How long does a scoping review take?
Scoping reviews typically take 3-12 months, somewhat shorter than systematic reviews because they do not require mandatory quality assessment or meta-analysis. However, the broader search scope may yield more records to screen, which can increase the timeline.
Can a scoping review lead to a systematic review?
Yes. Yes. This is one of the primary purposes of scoping reviews: to map the evidence landscape and identify specific sub-questions that warrant focused systematic review. A scoping review is often the first step before committing resources to a full systematic review.