Systematic vs. Scoping vs. Narrative Review: How to Choose

Students are often told to "do a systematic review" when what the supervisor wants is a thorough, well-organized literature chapter. The reverse also happens: a project that needs a defensible, reproducible answer gets a selective overview. The three labels describe different research designs with different questions, workloads and reporting rules. Picking the wrong one wastes time.

This guide compares the three types, works one topic through all three, and gives a decision path at the end.

The three review types in one paragraph each

Narrative (traditional) review. An overview of a topic built from sources the author selects and interprets. There is no requirement to find every study or to document the search. Its strength is argument: it can trace how a field developed, compare theories and build the case for a new study. Its weakness is that a reader cannot check whether the selection was balanced. Most thesis and dissertation literature chapters, and most "review" sections of journal articles, are narrative reviews.

Scoping review. A structured map of the evidence on a broad question. The search is comprehensive and documented, the screening follows stated criteria, and data are charted into tables. It usually does not judge the quality of each study or calculate a pooled result. The method comes from Arksey and O'Malley (2005), was refined by Levac and colleagues (2010), and has since been developed by JBI, whose current guidance is described by Peters and colleagues (2020) and set out in the JBI Manual for Evidence Synthesis.

Systematic review. A study in its own right that answers a focused question by identifying, appraising and synthesizing all the evidence that meets criteria fixed in advance. It has a registered protocol, searches several databases, uses two independent screeners, assesses risk of bias in each included study, and reports everything under PRISMA 2020. The Cochrane Handbook is the reference method for reviews of interventions.

Side-by-side comparison

Munn and colleagues (2018) published a widely used comparison. The first six rows below are their Table 1: the row labels are the paper's own, and the bracketed notes are its footnotes. The remaining rows are our summary, drawing on the PRISMA statements, Peters et al. (2020) and Borah et al. (2017).

On duration: Borah and colleagues analyzed 195 completed systematic reviews of medical interventions registered on PROSPERO and estimated a mean of 67.3 weeks from registration to publication, with a mean of five authors per review. Plan accordingly.

When each type is the right choice

Choose a systematic review when

Munn et al. list the purposes that justify a systematic review. In short, you need one when the answer will inform a decision and therefore has to be complete and unbiased:

• You are asking whether an intervention, exposure or test works, or how accurate or common something is.
• Studies disagree and you need to establish why, or what the overall result is.
• You want to confirm whether current practice is supported by evidence.
• The result will feed a guideline or policy.

The question must be narrow enough that the included studies are comparable. "Does cognitive behavioural therapy delivered by app reduce insomnia severity in adults compared with sleep hygiene education?" works. "How is technology used in sleep medicine?" does not.

Choose a scoping review when

Munn et al. give six indications for a scoping review:

1. To identify the types of available evidence in a given field.
2. To clarify key concepts and definitions in the literature.
3. To examine how research is conducted on a certain topic or field.
4. To identify key characteristics or factors related to a concept.
5. As a precursor to a systematic review.
6. To identify and analyse knowledge gaps.

If your aim is to map a young, messy or interdisciplinary literature, and you are not going to tell readers what works, a scoping review fits. If you catch yourself wanting to conclude that an intervention is effective, you need a systematic review, because a scoping review has not appraised the studies and cannot support that claim.

Choose a narrative review when

• The review is a chapter or section that sets up your own empirical study.
• The goal is conceptual: comparing theories, tracing a debate, proposing a framework.
• The literature spans disciplines and designs that cannot be reduced to one answerable question.
• You are working alone within a term or a year.

A narrative review is not a lesser product. It is a different one. It is judged on coverage of the key works, the quality of the synthesis and the clarity of the argument. The SANRA scale (Baethge, Goldbeck-Wood and Mertens, 2019) scores narrative reviews on six items, each rated 0 to 2: explanation of the review's importance, statement of its aims, description of the literature search, referencing, scientific reasoning, and presentation of relevant and appropriate endpoint data. It works well as a checklist for a thesis chapter, especially the third item. Two or three sentences saying which databases you searched, with which terms and date limits, let a reader judge how the sources were chosen.

The middle option: a systematized review

Grant and Booth's typology of 14 review types includes the "systematized review": one that attempts "to include one or more elements of the systematic review process while stopping short of claiming that the resultant output is a systematic review". They describe it as "typically conducted as a postgraduate student assignment, in recognition that they are not able to draw upon the resources required for a full systematic review (such as two reviewers)". You document the search, state inclusion criteria, show a flow diagram and may appraise quality, but you do not claim the independent double screening a full systematic review requires. If your supervisor asks for "a systematic literature review" in a solo thesis, this is usually what is achievable. Say so in your methods section.

One topic, three reviews

Take the topic of AI-generated feedback on student writing in higher education.

As a narrative review

Question: How has automated feedback on student writing been theorized and studied, and what does that imply for a study of generative AI feedback in first-year composition?

Approach: Search two or three databases plus Google Scholar, follow citations from recent key papers, and select the works that shaped the debate. Organize by theme: feedback theory, automated writing evaluation before 2022, generative AI studies since then, and student trust.

Output: A 6,000-word chapter ending in a stated gap and your research question. No flow diagram is needed, though a short paragraph describing the search helps.

As a scoping review

Question (PCC): In higher education students (Population), what research exists on generative AI feedback on writing (Concept) across countries and disciplines (Context)? Which designs, tools, outcomes and populations have been studied?

Approach: Write a protocol and post it on OSF. Search ERIC, Scopus, Web of Science and one computing database, plus grey literature such as conference papers. Two people screen titles and abstracts, then full texts. Chart each study's country, discipline, tool, design, sample and outcomes measured.

Output: A flow diagram reported under PRISMA-ScR, plus tables and charts that count the included studies by design, discipline, tool, population and outcome measured, so that readers can see which combinations have been studied and which have not. No claim about whether the feedback "works".

As a systematic review

Question (PICO): In undergraduate students (P), does feedback from generative AI tools (I), compared with instructor or peer feedback (C), improve scores on assessed writing quality (O)?

Approach: Register on PROSPERO. Search exhaustively. Include only controlled designs that report a writing quality outcome. Two reviewers screen and extract independently. Assess each study with a risk-of-bias tool such as RoB 2 or ROBINS-I. Pool effect sizes if the studies are similar enough, and rate the certainty of the evidence.

Output: A PRISMA 2020 flow diagram, a risk-of-bias table, a forest plot if pooling was possible, and a conclusion about the size and certainty of the effect.

The subject is the same. The three reviews have different questions, different amounts of labour and different things they are entitled to conclude.

A decision path

1. Is the review the main study, or the background to another study? Background: write a narrative review and document your search. Main study: go to step 2.
2. Do you want to answer a specific question about effect, accuracy, prevalence or experience? Yes: systematic review, go to step 4. No: go to step 3.
3. Do you want to describe what evidence exists, how it was produced, or how a concept is defined? Yes: scoping review. No: reconsider whether the question is clear enough yet. The research question guide can help.
4. Do you have a second reviewer and roughly a year? Yes: proceed with a systematic review. No: do a systematized review and label it accurately, or narrow the question until a rapid review is feasible.
5. Check PROSPERO, the Cochrane Library and JBI Evidence Synthesis for an existing or registered review on the same question. If a recent one exists, update or extend it instead of repeating it.

Common mistakes

• Calling a narrative review "systematic" because databases were searched. In Munn et al.'s comparison, a systematic review has a protocol, an explicit search, standardized extraction and mandatory critical appraisal. If those are missing, use "systematized" or "structured" instead.
• Drawing effectiveness conclusions from a scoping review. Without appraisal, you cannot weigh a small uncontrolled study against a large trial.
• Choosing a scoping review to avoid work. Broad questions return more records to screen.
• Writing the protocol after screening. The point of a protocol is that decisions are made before you see the results. Date-stamp it, even if only on OSF.
• Ignoring existing reviews. An umbrella review or an update may be more useful than a fourth systematic review of the same trials.

Where tools fit

Whatever the type, the mechanical parts are the same: running searches, removing duplicates, screening, and keeping track of what was decided and why. Reference managers such as Zotero handle deduplication. Screening tools such as Rayyan or Covidence support blinded dual screening for systematic and scoping reviews. For narrative and systematized reviews, the practical need is a record of what you searched and a place to group sources by theme. A synthesis matrix does the second job well.

References

• Arksey, H., & O'Malley, L. (2005). Scoping studies: towards a methodological framework. International Journal of Social Research Methodology, 8(1), 19–32. https://doi.org/10.1080/1364557032000119616
• Baethge, C., Goldbeck-Wood, S., & Mertens, S. (2019). SANRA: a scale for the quality assessment of narrative review articles. Research Integrity and Peer Review, 4, 5. https://doi.org/10.1186/s41073-019-0064-8
• Borah, R., Brown, A. W., Capers, P. L., & Kaiser, K. A. (2017). Analysis of the time and workers needed to conduct systematic reviews of medical interventions using data from the PROSPERO registry. BMJ Open, 7(2), e012545. https://doi.org/10.1136/bmjopen-2016-012545
• Grant, M. J., & Booth, A. (2009). A typology of reviews: an analysis of 14 review types and associated methodologies. Health Information & Libraries Journal, 26(2), 91–108. https://doi.org/10.1111/j.1471-1842.2009.00848.x
• Higgins, J. P. T., Thomas, J., Chandler, J., Cumpston, M., Li, T., Page, M. J., & Welch, V. A. (Eds.). Cochrane Handbook for Systematic Reviews of Interventions, version 6.5 (2024). https://www.cochrane.org/authors/handbooks-and-manuals/handbook/current
• Levac, D., Colquhoun, H., & O'Brien, K. K. (2010). Scoping studies: advancing the methodology. Implementation Science, 5, 69. https://doi.org/10.1186/1748-5908-5-69
• Munn, Z., Peters, M. D. J., Stern, C., Tufanaru, C., McArthur, A., & Aromataris, E. (2018). Systematic review or scoping review? Guidance for authors when choosing between a systematic or scoping review approach. BMC Medical Research Methodology, 18, 143. https://doi.org/10.1186/s12874-018-0611-x
• Page, M. J., McKenzie, J. E., Bossuyt, P. M., et al. (2021). The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. BMJ, 372, n71. https://doi.org/10.1136/bmj.n71
• JBI. JBI Manual for Evidence Synthesis (see the chapter on scoping reviews). https://jbi-global-wiki.refined.site/space/MANUAL
• Peters, M. D. J., Marnie, C., Tricco, A. C., Pollock, D., Munn, Z., Alexander, L., McInerney, P., Godfrey, C. M., & Khalil, H. (2020). Updated methodological guidance for the conduct of scoping reviews. JBI Evidence Synthesis, 18(10), 2119–2126. https://doi.org/10.11124/JBIES-20-00167
• Tricco, A. C., Lillie, E., Zarin, W., et al. (2018). PRISMA Extension for Scoping Reviews (PRISMA-ScR): checklist and explanation. Annals of Internal Medicine, 169(7), 467–473. https://doi.org/10.7326/M18-0850