Reporting Standards

What Is a PRISMA Flow Diagram?

The PRISMA flow diagram is a visual roadmap of your systematic review's search strategy. It maps out how records move from initial database search to the final included studies.

What the Diagram Is For

Journal editors and peer reviewers need transparency. They must know exactly where studies were lost and why. The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement standardizes this tracking.

🔍

1. Identify

Total records fetched from database queries.

✂️

2. Screen

Abstracts evaluated and duplicates removed.

⚖️

3. Assess

Full-text PDFs reviewed for eligibility criteria.

🎓

4. Include

Final studies selected for data extraction.

PRISMA 2020 Flow Diagram Example

Below is an example of a standard PRISMA 2020 flow diagram. It tracks records through the screening pipeline.

Phase 1: Identification
Database Searches PubMed, Scopus, WoS n = 1,420
Other Registries ClinicalTrials.gov, Registers n = 43
Duplicates Removed Merged automatically & manually n = 318
Phase 2: Title & Abstract Screening
Records Screened Titles and abstracts evaluated n = 1,145
Records Excluded Irrelevant to research n = 982
Phase 3: Full-Text Eligibility
Reports Sought for Retrieval PDFs requested/found n = 163
Not Retrieved Paywalled/no response n = 8
Reports Assessed for Eligibility Full text PDFs evaluated n = 155
Reports Excluded:
  • • Wrong outcome: 83
  • • Wrong design: 32
  • • No control: 17
Phase 4: Included Studies
Studies Included in Review Final papers selected for synthesis n = 23

Prerequisite Counts for Your Diagram

To build your PRISMA diagram, you must track these numbers during screening. Do not rely on guesswork at the end of your review.

Identification Counts

Database result totals, register counts, and any reference citations retrieved via citation chasing (snowballing).

Deduplication Count

The total count of duplicates removed before abstract screening begins, including those merged automatically.

Abstract Exclusions

The total number of titles and abstracts evaluated, and how many did not meet eligibility criteria.

Full-Text Exclusions with Reasons

The count of full-text papers read but rejected. You must provide specific counts per rejection reason (e.g., wrong cohort, incorrect intervention).

Common Reporting Mistakes

Mixing records and studies: A search result (record) is not a study. Keep references (n = records) separate from final papers (n = studies) in your diagram.
Omitting exclusion reasons: Peer reviewers will reject diagrams that list "full texts excluded: 40" without breaking down the specific scientific reasons.

Build One Instantly

If you already have your numbers, use Lumina's free online PRISMA generator to build a publication-ready SVG/PNG diagram.

Open Free PRISMA Tool