Purpose of a literature review
A literature review explains what is already known about your topic, how researchers have approached it and where gaps or disagreements remain. It sets up your own study by showing why it is needed.
It is not a list of article summaries. A strong review is organised around ideas, compares and evaluates studies, and leads the reader to your research question.
Finding and selecting sources
Start with keywords from your research question and add synonyms. Search databases your university subscribes to, such as Scopus, Web of Science, ScienceDirect or Google Scholar, and use your library's guides.
Prefer peer-reviewed articles and recent work, often the last five to ten years, plus key older studies. Check the abstract, method and findings before including a source. Record each source with its aim, method, findings and limitations in a spreadsheet or a reference manager such as Zotero or Mendeley.
Organising by theme
Group sources by theme, concept or debate, not by author or date. For example, a review on online learning might have sections on student engagement, technology access and assessment. Under each theme, discuss what studies agree on, where they differ and why.
Create a matrix with studies in rows and themes in columns to see patterns. Use headings so the reader can follow your structure.
Synthesis vs summary
Summary describes one study at a time: "Lee (2020) found X. Tan (2021) found Y." Synthesis connects studies: "Although Lee (2020) and Tan (2021) both found X, they differ on Y, probably because of Z."
To synthesise, compare methods, samples and contexts, point out agreement and conflict, and give your judgment on the quality of evidence. Each paragraph should make a point and use several sources to support it.
Identifying the research gap
A research gap is a question that existing studies leave unanswered. It may be a missing population, context, variable, method or an unresolved conflict in the findings.
State it explicitly: "Few studies have examined X among Malaysian undergraduates; most research focuses on Y." Support the claim with the review itself, and then link the gap to your research objectives. Check that the gap is real by searching more widely before claiming no one has studied it.
Structure and example outline
A typical review has:
- An introduction explaining its scope and organisation.
- Three to five thematic sections with synthesis.
- Theoretical or conceptual framework, if relevant.
- A summary that identifies the gap and leads to your research questions.
Example outline for a study on remote work and productivity: 2.1 Definitions; 2.2 Remote work and employee productivity; 2.3 Moderating factors (management support, home environment); 2.4 Research gap and conceptual framework.
Checklist
Check that:
- Your search was systematic and recorded.
- Sources are recent, relevant and mostly peer-reviewed.
- The review is organised by theme.
- You compare and evaluate instead of summarising.
- The gap is clear and supported.
- It leads to your research questions or hypotheses.
- Citations match the reference list and follow your style.