To approach a literature review, set a clear question, map sources, evaluate quality, synthesize themes, and write with a clear line of argument.
What A Literature Review Does
A literature review builds a reasoned account of what scholars have found, how they studied it, and where the conversation is heading. It is not a list. It is a narrative that links studies to a guiding question and makes the line of reasoning easy to follow. For a crisp primer, see the UNC Writing Center guide.
Your job is to choose sources with intent, explain their methods and claims, and group them into patterns. Readers should see why each source is there, what it adds, and how it relates to others. Clarity beats volume.
Common Review Types At A Glance
| Type | Main Goal | Typical Use |
|---|---|---|
| Narrative | Summarize and connect themes across studies | Course papers, theses in early stages |
| Scoping | Map breadth, terms, and gaps | New fields, topic mapping |
| Systematic | Answer a tight question with transparent methods | Graduate projects, grant work |
| Meta-analysis | Combine comparable effect sizes | Quantitative disciplines |
| Theoretical | Compare models and definitions | Concept clarification |
| Methodological | Contrast research designs and tools | Planning new studies |
Approaching A Literature Review: Practical Method
1) Nail The Question
Phrase a tight question that names the population, concept, method, and setting where relevant. Health fields often use PICO or a close cousin. The question sets your inclusion rules and your outline later on.
2) Map The Field
List core concepts, synonyms, and opposites. Add controlled vocabulary where your databases use it. Draw a quick concept map.
3) Build Search Strings
Join terms with AND, OR, and NOT. Use quotation marks for phrases and a wildcard to catch variants. Test alternate strings in one database before you scale. If you plan a systematic route, plan to record hits and screening in a PRISMA 2020 flow diagram.
4) Pick Databases On Purpose
Match sources to your field: multidisciplinary indexes for broad sweeps; subject databases for depth; Google Scholar for tracing citations; specialist repositories for theses or reports.
5) Run, Log, Refine
Search, then log the date, database, string, and hit count. Skim the first two pages of results. Adjust terms and filters. Repeat in the next database.
6) Screen With Clear Rules
Set inclusion and exclusion rules before you screen. Apply them to titles and abstracts, then to full texts. Record reasons when you exclude a study. This makes your choices transparent and repeatable.
7) Extract And Compare
Create a matrix with author, year, setting, sample, method, measures, and main claim. Add columns for strengths, limits, and notes. Side-by-side entries make patterns and conflicts visible.
8) Synthesize Patterns
Group studies by theme, method, theory, or result. Ask what explains agreement and where differences arise. Point to likely causes: sample size, measures, context, or design.
9) Shape The Structure
Pick an order that matches your question. Options include thematic, methodological, or chronological. Use a short signpost paragraph to tell readers what comes next and why.
10) Draft And Revise
Write topic sentences that make a claim. Weave summaries with brief evaluation. Signal contrast and connection. Paraphrase with care and quote sparingly. Cite as you write to avoid backtracking later.
Quality Checks That Save Time
Ask if each study fits the question, uses sound measures, and reports enough detail to judge the claim. Watch for small samples, weak comparators, self-report bias, and missing data. Note funding and conflicts.
Cross-check facts and definitions across sources. If two strong studies disagree, show the difference and suggest plausible reasons. That is stronger than forcing a false consensus. Many writing centers share checklists that help with quick source vetting.
Structuring The Write-Up
Open With Purpose
Start with the question, scope, and a one-sentence thesis that states your main take. Define boundaries: time frame, region, and study types included. Name the selection logic in plain terms.
Build The Middle
Use sections that match your chosen scheme. Each section should advance the thesis. Within sections, move from big claims to finer points. Tie studies together with short signposts like “by contrast,” “a related line,” or “a different design finds.”
Close With A Clear Payoff
State what the field now knows, what remains unsettled, and what kind of study would move things forward. Link this closing to your original question so the arc feels complete.
Using An Evidence Matrix
An evidence matrix keeps facts straight while you read. Pick columns that match your question and methods in your field. Typical columns include population, intervention or driver, comparator, outcome, and context. Many writers add theory used, measures, and sample size.
Color-code rows by theme or method. Add a tag column for quick filters. When a claim spans several studies, the matrix shows it at a glance. When one study sticks out, the matrix helps you stage a fair read of why.
Style And Tone That Build Trust
Use plain verbs. Avoid hedging that fogs meaning, but do not overstate. Attribute claims with “finds,” “reports,” or “argues.” Keep quotes short and reserve them for lines that carry special weight or precision.
Keep sentences varied in length. Use parallel structure in lists. Prefer concrete nouns over abstractions. Replace filler with data, numbers, or short examples.
Citations, Paraphrases, And Ethics
Cite the source of each idea, claim, or number. When paraphrasing, change structure and wording, then compare against the original to check distance. Use a reference manager so you can switch styles without retyping. Store PDFs with notes so you can trace a quote back to the page fast.
If you review your own prior work, label it. If you include preprints, say so. If you draw on grey sources, name the venue and the screening you used. Transparency keeps the record clean.
When The Review Sits Inside A Larger Project
Align the scope with the paper’s research question or thesis chapter aim. Trim tangents. Point out the gap your study fills, but ground that claim with citations. End by linking your methods to the needs you just surfaced.
Common Pitfalls And Quick Fixes
- Too broad: Shrink the question or limit the time window.
- Too descriptive: Add short evaluation of methods and measures.
- Patchwork flow: Group by theme and add signposts.
- Outdated set: Rerun searches before submission.
- Missing classics: Trace citations from recent reviews and capturable landmarks.
- Method mismatch: Split the review by method where needed.
Tools And Simple Workflow
Use a reference manager to store citations and PDFs. Try a note app with tags for themes. Draft the evidence matrix in a spreadsheet. Keep a single document for your log. Use consistent file names so you can find items later.
When figures help, add one diagram: a concept map, a timeline, or a PRISMA-style flow if your process warrants it. One clear visual can carry a lot of load without clutter.
Defining Scope And Boundaries
Set limits you can defend before you start reading. Time span, languages included, regions, populations, and study types all shape the set you will read. If you study a fast-moving topic, use a recent window and plan a refresh cycle. If you need depth, expand the window but narrow the concept list. Write your choices in the log so future readers can trace them.
Name the theories and core terms you accept and those you treat as outside scope. If a term carries multiple meanings, pick one and state it at the top of the review. That small move prevents drift and makes screening faster later on.
Handling Conflicting Evidence
Not all findings align, and that is fine. Put clashing results in the same section and compare the nuts and bolts that shape outcomes. Samples, measures, exposure length, and setting often explain gaps. Report any re-analyses or registered reports that revisit older claims. If a study stands alone, mark it as tentative and describe what new data would test it well.
When a claim repeats across many small studies, weigh the total body of evidence instead of the loudest single paper. If methods cluster by region or school, note that pattern and suggest cross-checks in a different setting or with a different design.
Timebox And Milestones
Work in stages with clear limits. Give the mapping step a set number of hours, the search loop a set number of sessions, and screening a fixed daily batch. Draft the matrix as you screen so writing starts early. Set a midpoint check where you test the outline against the studies in hand. End with one buffer week for final searches and a quick pass through the log, matrix, and references.
Small, repeatable tasks beat marathon sessions. A half hour each day on the log or the matrix keeps momentum. Share the outline with a classmate or mentor and ask one question: does the sequence make sense given the evidence listed in the matrix? Short check-ins keep errors small and progress steady every week.
Search And Screening Log (Template)
| Step | What To Record | Tip |
|---|---|---|
| Plan | Question, scope, inclusion rules | Keep a dated note |
| Search | Database, string, filters, hits | Copy the exact string |
| Screen | Numbers kept and excluded | List reasons once, reuse |
| Extract | Fields in your evidence matrix | Set columns before reading |
| Synthesize | How you grouped studies | Write a one-line rationale |
| Write | Outline and section notes | Link notes to citations |
Bring It All Together
A sound literature review rests on a tight question, a transparent search, fair screening, careful reading, and a clear write-up. Follow the loop: plan, search, screen, extract, synthesize, write. When each link is solid, readers trust your take and can build on it with ease.