No, literature reviews are secondary sources that synthesize primary research across studies.
Writers and students ask this all the time because instructors and style guides treat source types differently. Here’s the short take: a literature review gathers, summarizes, and compares original studies; it does not present new, first-hand evidence. That makes it a secondary source in nearly every field. A few edge cases create confusion—like meta-analyses or methodological notes inside a review—so this guide spells out where the lines sit and how to cite and use each type with confidence.
Quick Map Of Source Types (So You Can Classify Fast)
This table keeps the moving parts straight. Use it as a fast check before you write or cite.
| Source Type | What It Does | Typical Use |
|---|---|---|
| Original Research Article | Reports new data from experiments, surveys, fieldwork, or archives | Evidence for claims; methods and results |
| Dataset / Raw Materials | Uninterpreted numbers, transcripts, images, artifacts | Direct analysis, replication, re-use |
| Interview / Oral History | First-hand testimony recorded and transcribed | Quotations, narrative evidence |
| Lab Notebook / Field Notes | Contemporaneous records of procedures and observations | Procedural detail; audit trail |
| Literature Review | Synthesizes prior studies without generating new primary data | Context, gaps, consensus, debate |
| Systematic Review / Meta-analysis | Uses a protocol to search, screen, and pool results across studies | Decision support; evidence grading |
| Reference Work (Handbook, Encyclopedia) | Summarizes what’s known with citations | Background, definitions |
| Textbook / Guide | Broad synthesis for teaching | Orientation, study |
What “Primary” And “Secondary” Actually Mean
“Primary” points to proximity. A primary source puts you as close as possible to the event, experiment, or object. Think a randomized trial’s results table, a poet’s draft, a census microfile, or a soil sample reading. A “secondary” source stands one step back, weighing and weaving those first-hand materials. A literature review fits that second bucket by design. In health sciences, systematic reviews follow a published method to reduce bias while they summarize trials; that still counts as a synthesis rather than new, first-hand evidence.
Why Reviews Sit In The Secondary Column
A review collects studies, sets inclusion rules, extracts findings, and compares results. Even when it runs statistics across papers (a meta-analysis), the numbers come from earlier experiments or observations. The work adds order and clarity, not brand-new measurements. That’s the core reason your bibliography should label literature reviews as secondary.
How This Plays Out Across Disciplines
In biomedical fields, a review usually states a protocol, lists databases, shows a flow diagram, and grades evidence. In the humanities, a review traces schools of thought and curates sources. In social sciences, a review often maps variables, theories, and methods across studies. Different surface forms, same posture: summarizing someone else’s first-hand work.
Are Literature Reviews Primary Sources? Nuances By Field
You’ll see the phrase “Are literature reviews primary sources?” in assignment sheets, grading rubrics, and library guides. The answer stays no across fields, but the way you use a review shifts a bit:
Health And Medicine
Systematic reviews and meta-analyses sit near the top of evidence pyramids because they combine many trials with tight methods. They’re still secondary. When guidelines lean on reviews, they do it to summarize many primary studies at once. If you quote a pooled effect size, you’re citing a secondary synthesis of primary experiments.
Social Sciences
Reviews compare surveys, experiments, and ethnographies to show patterns and contradictions. They might cluster studies by method, sample, country, or time period. That work helps you scope a project and avoid duplicated designs, but it’s still a step removed from first-hand data.
Humanities
In literary studies, history, and philosophy, a review pulls threads across monographs, editions, and archival pieces to show where arguments stand. It points to the primary texts and artifacts you’ll analyze. It doesn’t replace digging into those materials.
Are Literature Reviews A Primary Source? Field Rules
This near-match query pops up in search too. Think of it as a check on corner cases. The safe practice: treat reviews as secondary unless they contain a distinct element that shifts part of the work into primary territory, listed below.
Edge Cases That Confuse Readers
Some reviews embed features that feel primary. Here’s how to read them:
- New Corpus Or Data Extraction: A review might release a machine-readable dataset it built from the included studies. The dataset is primary; the narrative review remains secondary.
- Reanalysis Of Shared Data: If authors obtain raw trial data and re-run models, that reanalysis can count as primary analysis. The rest of the review still synthesizes prior papers.
- Methods Paper Disguised As A Review: Some pieces are half tutorial, half survey. The teaching component doesn’t add new evidence; it clarifies techniques.
- Overviews Of Reviews: These gather multiple systematic reviews. They sit another step away and are solidly secondary (some libraries call them tertiary).
How To Decide What You’re Holding
When a PDF lands on your screen, run a three-step check:
Step 1: Scan For First-Hand Evidence
Look for a “Methods” section that describes participants, instruments, or archives the authors accessed themselves. Check for a “Results” section with new tables and figures created from data the authors collected. If you can’t find that, you’re likely reading a secondary source.
Step 2: Check The Inclusion Logic
If you see database names, search strings, screening criteria, and a PRISMA-style flow diagram, you’re reading a systematic review. That’s a disciplined synthesis, still not a primary study.
Step 3: Look For Reusable Materials
Did the authors publish a supplementary dataset or code they built from the papers they reviewed? You can cite that dataset as primary while still treating the write-up as secondary.
When A Review Is Useful (And When It Isn’t)
Use reviews to map a topic fast, locate clusters of evidence, and spot gaps where your project can contribute. Use the cited primary sources to test claims, re-analyze data, or extend a method. Skip reviews when you need the exact instruments, stimuli, or code used in a study; go straight to the primary papers for that level of detail.
Citation And Writing Moves That Save You Time
Writers often mix up how to cite a review versus a primary article. Keep these moves handy.
Signal Phrases That Clarify Source Type
- Primary: “In a randomized trial of 650 patients, Smith et al. report…”
- Secondary: “In a literature review of 52 studies, Kim and Lee summarize…”
- Meta-analysis: “A pooled estimate across 18 cohorts shows…”
Quoting And Paraphrasing
When you pull wording from a primary article, cite that article. When you repeat a conclusion that a review draws by combining studies, cite the review. If your claim depends on a single experiment inside a review, click through and cite the original too.
Common Scenarios, Clear Rulings
These quick rulings help you classify tricky cases without second-guessing.
| Scenario | Primary? | Why |
|---|---|---|
| A narrative literature review of climate policy papers | No | Summarizes prior studies; no new first-hand evidence |
| A systematic review with a meta-analysis of trial results | No | Pools published outcomes; still secondary synthesis |
| A review that releases a coded dataset of all included studies | Mixed | Dataset is primary; narrative is secondary |
| An overview of systematic reviews on a topic | No | One step further removed; often labeled tertiary |
| A methods primer embedded inside a literature review | No | Teaches technique; no new evidence |
| A review that re-analyzes shared raw data from original authors | Partly | Reanalysis can be primary; synthesis remains secondary |
| A textbook chapter summarizing the field | No | Broad synthesis; background only |
Practical Tips For Assignments And Proposals
Many prompts ask you to “use at least five primary sources.” If you lean on reviews to pick those sources, that’s smart. Just make sure your citations and arguments rest on the primary studies you selected. Keep the review in your list too—it shows you surveyed the field and sets context—but don’t let it stand in for the evidence your claims depend on.
Building A Balanced Reference List
- Start with one or two high-quality reviews to map the terrain.
- From those, pull the seminal experiments, key datasets, or core texts that match your question.
- Add one reference work for definitions so your terms stay consistent.
Writing With Precision
Spell out which sources carry your proof. A sentence like “Prior work shows a reduction in symptoms” is vague. Upgrade it to “Across 12 trials summarized in a meta-analysis, pooled results show a reduction in symptoms; Study X reports the largest effect under weekly dosing.” Now your reader can see the secondary and the primary inputs.
Evidence Standards And Where To Read More
When you need a model of how systematic reviews work, the Cochrane Handbook lays out the method from protocol to synthesis; see the guidance on how reviews collate empirical evidence and use steps to manage bias (Cochrane chapter on starting a review). If you’re sorting background sources, a library guide that distinguishes primary, secondary, and tertiary materials helps you label textbooks and encyclopedias correctly; one quick primer is Cornell’s page on tertiary sources (tertiary sources guide).
Short Answers To Popular Questions
Can You Cite A Literature Review In A Methods Section?
Yes. Use a review to justify choices like outcome measures or inclusion criteria. Then cite primary studies for the instruments or protocols you adopt.
Do Meta-Analyses Count As Primary?
No. They combine published results across studies. The pooled estimate is new, but it’s built from prior measurements. Treat the meta-analysis as a strong secondary source, and still cite key trials.
Do Instructors Ever Ask You To Avoid Reviews?
Sometimes. That instruction pushes you to read the studies yourself. You can still use a review to find those studies; you just won’t quote the review as your main evidence.
Recap You Can Use Right Now
Are literature reviews primary sources? No. A review is a synthesis of other people’s first-hand work. Use reviews to map a topic, gather the right articles, and report consensus. Build your claims on primary materials—trial results, datasets, archival texts—so your paper stands on first-hand evidence. Keep one thought handy for searches, assignments, and peer feedback: a review points you to the evidence; it isn’t the evidence itself.