The PRISMA 2020 statement provides four official flow diagram templates, a significant expansion from the single template in the original 2009 PRISMA guidelines. Each template is designed for a specific type of systematic review, and selecting the correct one is essential for accurate, transparent reporting. Using the wrong template is one of the most frequent errors in PRISMA flow diagrams identified during peer review.
This guide explains each of the four PRISMA 2020 flow diagram templates, when to use them, what fields they include, and provides a decision framework for choosing the right one for your review.
Why Four Templates?
The original PRISMA statement assumed all systematic reviews followed a similar structure: search databases, screen results, assess eligibility, include studies. However, systematic review methodology has evolved significantly since 2009:
- Many reviews now include other sources beyond databases, such as citation searching, grey literature, organizational websites, and trial registries
- Updated systematic reviews have become common, requiring a way to distinguish between previously identified and newly identified evidence
- Automation tools are increasingly used for deduplication and pre-screening, requiring documentation in the flow diagram
PRISMA 2020 addresses these developments with four templates based on two binary decisions. For the full context of these changes, see PRISMA 2020 vs original PRISMA: what changed.
Template 1: New Review, Databases and Registers Only
Use when: You are conducting an original (not updated) systematic review and your search was limited to bibliographic databases and registers.
Structure: Single-column layout with one identification source (databases/registers). No "other sources" column.
Fields included:
- Records identified from databases (with per-database breakdown)
- Records from registers
- Duplicates and pre-screening removals
- Records screened and excluded
- Reports sought and not retrieved
- Reports assessed for eligibility with exclusion reasons
- Studies and reports included
Typical use case: A focused clinical review searching PubMed, Embase, and Cochrane CENTRAL without additional citation searching or grey literature.
Template 2: New Review, Databases and Other Sources
Use when: You are conducting an original systematic review and you searched databases/registers AND also used other sources such as citation searching, websites, organizational contacts, or grey literature.
Structure: Two-column layout. Left column for databases/registers, right column for other sources. Both columns flow into a shared "Included" box at the bottom.
Fields included:
- Everything in Template 1, PLUS:
- Records identified from websites, organizations, and citation searching
- Separate retrieval and eligibility assessment for other sources
Typical use case: A comprehensive systematic review that supplemented database searching with backward/forward citation searching and grey literature from organizational websites. This is the most commonly used template.
Template 3: Updated Review, Databases and Registers Only
Use when: You are updating a previously published systematic review and your new search was limited to databases/registers.
Structure: Similar to Template 1 but includes an additional section for studies and reports from the previous version of the review. The "Included" box shows both new and total studies/reports.
Fields included:
- Everything in Template 1, PLUS:
- Studies included in the previous version of the review
- Reports from the previous version
- New studies included
- Total studies included (previous + new)
- Total reports
Typical use case: A Cochrane review update where the original review has been published and the update searches the same databases for new evidence.
Template 4: Updated Review, Databases and Other Sources
Use when: You are updating a previously published systematic review and your new search included both databases/registers and other sources.
Structure: The most complex template. Combines the two-column layout of Template 2 with the previous studies section of Template 3.
Fields included:
- Everything in Templates 2 and 3 combined
- Previous studies, records from databases and other sources, separate retrieval and eligibility for both columns, new and total included studies
Typical use case: A comprehensive review update that expanded the search beyond the original databases to include citation searching, grey literature, and other sources.
Decision Framework: Which Template Should I Use?
Follow this two-step decision process:
Step 1: Is your review new or an update?
- New: This is the first version of this systematic review → Templates 1 or 2
- Updated: You are updating a previously published systematic review → Templates 3 or 4
Step 2: What sources did you search?
- Databases/registers only: You searched bibliographic databases (PubMed, Embase, etc.) and/or trial registries, with no additional sources → Templates 1 or 3
- Databases + other sources: You also used citation searching, grey literature, websites, organizational contacts, or any other source beyond databases → Templates 2 or 4
| Databases Only | Databases + Other Sources | |
|---|---|---|
| New Review | Template 1 | Template 2 |
| Updated Review | Template 3 | Template 4 |
Common Questions About Template Selection
Does citation searching count as "other sources"? Yes. Forward citation searching (checking who cited included studies) and backward citation searching (checking reference lists) are classified as other sources, not database searching.
What if I only found records from databases but also tried other sources? If you searched other sources but found zero records, you should still use the "databases + other sources" template to document that these sources were searched.
What about trial registries? Searching clinical trial registries (e.g., ClinicalTrials.gov, WHO ICTRP) is classified as "registers" in the databases/registers column, not as other sources.
You can create any of these templates using our free PRISMA diagram generator tool. Simply select your template type and the form will show the appropriate fields.
Frequently Asked Questions
Can I switch templates after starting my diagram?
Yes. In our free generator tool, you can change the template type at any time and the form fields will update accordingly. Your entered data is preserved where fields overlap between templates.
What is the most commonly used PRISMA 2020 template?
Template 2 (new review, databases + other sources) is the most commonly used, as most systematic reviews include some form of supplementary searching beyond databases, such as checking reference lists of included studies.
Do I need a different template for scoping reviews?
Yes. Scoping reviews use PRISMA-ScR (PRISMA Extension for Scoping Reviews), which has a different structure. See our guide on PRISMA-ScR for scoping reviews for details.
Where can I find the official PRISMA 2020 template files?
The official templates are available at prisma-statement.org. You can also generate compliant diagrams directly using our online PRISMA 2020 diagram builder.