Extended definition
PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) is the international standard guideline for reporting systematic reviews and meta-analyses. It replaced the QUOROM guideline (1999); the first PRISMA version was published in 2009 (Liberati et al., PLoS Medicine / BMJ) and the current version is PRISMA 2020 (Page et al., 2021, BMJ). The guideline consists of a 27-item checklist distributed across seven sections (title, abstract, introduction, methods, results, discussion, other information), plus the PRISMA flow diagram documenting the process of identification, screening, eligibility, and inclusion of studies. PRISMA 2020 expanded coverage to include non-traditional searching (citations, author contact, trial registries), transparent reporting of protocol versions, and items on evidence certainty (GRADE). Official extensions exist for specific cases: PRISMA-ScR (scoping review), PRISMA-NMA (network meta-analysis), PRISMA-IPD (individual patient data), PRISMA-DTA (diagnostic test accuracy), PRISMA-Equity, PRISMA-Children, PRISMA-Search.
When it applies
PRISMA applies to any systematic review or meta-analysis submitted to a health journal — effective requirement of virtually all Q1/Q2 since 2010. It applies to other fields (social sciences, education, environmental sciences, software engineering) with growing adoption, especially through the applicable extensions. It applies in systematic review proposals for registration in PROSPERO or OSF — protocols should follow PRISMA-P (Protocols). It applies in methodological training: PRISMA is the standard organizing structure in systematic review courses. ICMJE explicitly recommends PRISMA as a reporting guideline.
When it does not apply
PRISMA is a reporting guideline, not a conduct protocol — it does not apply as a methodological recipe for conducting a review. For conduct, the Cochrane Handbook (health) or field-specific guidelines are appropriate. Standard PRISMA does not apply directly to review types outside systematic review + meta-analysis — official extensions cover specific cases (scoping review uses PRISMA-ScR). It does not apply to narrative review, theoretical essay, or bibliographic survey in thesis introduction. It does not apply as a quality certificate automatically — technically following the checklist without real methodological rigor produces a “PRISMA-compliant” but substantively weak review.
Applications by field
— Health: mandatory standard at Cochrane, BMJ, JAMA, Lancet, NEJM, and field Q1/Q2; PRISMA 2020 quickly replaced PRISMA 2009. — Education: EPPI-Centre adopts PRISMA with adaptations; top-tier educational research journals require it. — Software engineering: Kitchenham guidelines are complemented by PRISMA when submission targets interdisciplinary journals. — Public health and policy: PRISMA-Equity as an extension for equity-focused analyses.
Common pitfalls
The first pitfall is treating PRISMA as an administrative checklist after the review is done — well-applied PRISMA guides reporting during the process, not retroactively. The second is confusing PRISMA with PRISMA-P (Protocols) — the former is for reporting the final study; the latter for protocol registration. The third is incomplete flow diagrams: indicating numbers at each stage (identified, screened, excluded with reason, included) is a specific and auditable requirement. The fourth is not using the appropriate extension for the review type: using standard PRISMA in a scoping review instead of PRISMA-ScR confuses readers about scope and expectations. The fifth is PRISMA without protocol preregistration: PROSPERO or OSF before the search is modern standard practice; without it, the review has reduced credibility even when “PRISMA-compliant”.