PRISMA-ScR (PRISMA Extension for Scoping Reviews)

What it is

PRISMA-ScR is the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews, published by Tricco and colleagues in 2018 (Annals of Internal Medicine). It is an official EQUATOR Network reporting guideline, developed by a Joanna Briggs Institute (JBI)/PRISMA working group through a Delphi process and maintained alongside the wider PRISMA family at prisma-statement.org. The checklist comprises 20 essential items plus 2 optional items organized into the familiar PRISMA sections: title, abstract, introduction (rationale, objectives), methods (protocol/registration, eligibility, information sources, search, selection of sources, data charting, data items, critical appraisal if done, synthesis of results), results (selection, characteristics, results of individual sources, synthesis), discussion (summary, limitations, conclusions), and funding. Crucially, PRISMA-ScR is a reporting standard: it specifies what must appear in the manuscript so that a reader can judge what was done and reproduce it. It is not a methodology, a critical-appraisal/risk-of-bias instrument, or a quality score.

When to use

Use PRISMA-ScR when the deliverable is a scoping review — an exploratory synthesis whose aim is to map the breadth and nature of evidence, clarify concepts, identify knowledge gaps, or examine how research on a topic has been conducted, rather than to answer a focused effect-estimate question. Decision rules versus siblings: (1) If you are reporting a systematic review or meta-analysis of effects, use PRISMA 2020, not PRISMA-ScR. (2) If you are reporting the protocol of a systematic review, use PRISMA-P; PRISMA-ScR has no separate protocol extension, so scoping-review protocols are typically written against JBI scoping-review methodology and registered (e.g., on OSF) with PRISMA-P used adaptively. (3) Scoping reviews do not require a pooled estimate, a PICO-driven question, or a formal risk-of-bias assessment, although appraisal may be reported (item 12 is conditional). PRISMA-ScR applies across decision contexts where a scoping review is the chosen evidence product: peer-reviewed journals, HTA/payer landscape and gap analyses that precede a full systematic review, and regulatory or methods-mapping work (e.g., scoping the published RWE evidence base for a therapeutic area before designing a pharmacoepidemiologic study). It does not directly govern primary FDA/EMA non-interventional study submissions — those are reported under STROBE/RECORD-PE/HARPER and ISPOR/ISPE good-practice guidance.

What it requires

The checklist enforces transparent disclosure of the review's machinery. Design transparency: a stated rationale and explicit objectives framed (commonly) by population/concept/context; pre-specification via a protocol and its registration/availability; explicit eligibility criteria with justification. Search reproducibility: all information sources with dates of coverage, and a full electronic search strategy for at least one database, presented verbatim so it can be re-run. Selection and charting: the process for screening and selecting sources of evidence, the data-charting method (the scoping-review analogue of extraction — what was charted, by whom, and how charting was piloted and calibrated), and a clear account of how results were summarized (typically narrative/tabular/graphical mapping rather than statistical pooling). Flow accounting: a PRISMA-style flow diagram tracing records identified, screened, excluded with reasons, and included — the discipline that makes the evidence map auditable. Conditional appraisal: if critical appraisal of sources was performed, the method and results must be reported (and authors should state explicitly when it was not done). For scoping reviews built on real-world data sources or RWE literature, the same charting rigor should capture data-fitness descriptors of the included studies — design, data source (claims/EHR/registry), phenotype/algorithm definitions, time-zero handling, and stated estimands — so the map is informative for downstream method selection.

When NOT to use — limitations and common misapplications

(1) It is a reporting checklist, not a risk-of-bias tool and not a quality score. Ticking all 22 items certifies disclosure, not validity; a fully PRISMA-ScR-compliant scoping review can still rest on a biased or non-reproducible search. Do not sum the items into a "quality score." (2) Completing the checklist does not make the underlying evidence causal or decision-grade. A scoping review maps what exists; it does not synthesize effect sizes, grade certainty (no GRADE), or support a comparative-effectiveness claim — use a systematic review/meta-analysis for that. (3) Wrong-extension errors: using PRISMA-ScR to report a synthesis that actually estimates effects (should be PRISMA 2020), or forcing a focused effect question into the scoping format to avoid meta-analytic and risk-of-bias obligations. (4) Checklist-as-theater: pasting a completed checklist into an appendix while the search strategy is not reproducible, the flow numbers do not reconcile, or charting was undocumented. (5) Mis-scoping: labeling a review "scoping" to sidestep PROSPERO registration or risk-of-bias assessment when the question is genuinely about effects. (6) PRISMA-ScR governs reporting of the review; it imposes no standards on the primary RWE studies it includes — those are appraised against their own reporting and good-practice guidance.

How it maps to this catalog

PRISMA-ScR sits at the evidence-synthesis layer; its requirements point downward to the primary-study concepts whose presence (or absence) a scoping review of RWE should chart and that any included study must satisfy. Map item-by-item: the eligibility / data-charting items should capture each included study's design and data-fitness — implemented here by `claims-analysis` (administrative-claims data structure and fitness-for-use) and `medicare-ffs-ma-commercial-claims-differences-rwe` (data-source heterogeneity to record when charting); the objectives/concept framing for comparative RWE maps to `active-comparator-new-user` and `target-trial-emulation` as the design templates a mature evidence map should distinguish; phenotype/algorithm transparency that the charting form should extract is implemented by `diagnosis-phenotype-algorithm-1ip-2op-time-window-rwe` and `claims-outcome-algorithm-ppv-sensitivity-rwe`; estimand clarity of included studies maps to `estimands-ate-att-intercurrent-events-rwe` and `estimand-analysis-traceability-rwe`; attrition/flow accounting parallels `attrition-and-loss-to-follow-up-rwe` and `database-feasibility-attrition-funnel-rwe`; and confounding-control sophistication worth charting maps to `high-dimensional-propensity-score-hdps-rwe`. Applied note for claims/EHR/registry RWE: when scoping a therapeutic area's real-world evidence, build the charting form to extract, per study, the data source and provenance, the operational phenotype/outcome algorithm with validation metrics (PPV/sensitivity), the time-zero/new-user rule, the comparator strategy, the declared estimand, and the attrition funnel — this turns a PRISMA-ScR-compliant map into a directly actionable input for designing the confirmatory study, rather than a bibliography.