How to Write a Scoping Review

A scoping review maps the available evidence on a broad topic: what has been studied, how, where and what gaps exist. It uses a systematic, transparent process but usually does not appraise study quality or estimate effects.

The five stages (a widely used framework)

1. Identify the research question. Broad but clear, with a defined concept, population and context.
2. Identify relevant studies. A comprehensive, documented search across several databases and other sources.
3. Select studies. Explicit eligibility criteria, preferably with two reviewers.
4. Chart the data. Extract variables into a form agreed in advance.
5. Collate, summarise and report. Descriptive numerical summary plus a thematic account, with implications for research, practice and policy.

An optional sixth step involves consulting stakeholders.

Protocol and reporting

Write and, where possible, publish or register a protocol before the search. Report the review with the PRISMA-ScR checklist (see PRISMA-ScR Checklist Explained) and include a flow diagram.

Illustrative example

Invented for teaching. Question: "What is known about community-based interventions for hypertension in sub-Saharan Africa?" The team searches four databases and grey literature, screens 2,400 records in duplicate, charts 85 included studies (design, setting, intervention, outcome) and finds that most are pilot studies with short follow-up and few report cost. The review recommends larger trials and cost reporting.

What it cannot do

It does not usually assess risk of bias or pool effect sizes, so it cannot say which intervention works best.

Common pitfalls

• A question so narrow that it is really a systematic review, or so broad that it cannot be completed.
• Drawing effectiveness conclusions.

Key takeaways

• Scoping reviews map evidence and gaps using a transparent method.
• Use a protocol and PRISMA-ScR.

This page is general educational information about research methods. It is not medical, legal or regulatory advice; follow your institution's ethics board and your target journal's instructions.