An Extended Essay in Psychology most commonly takes one of two forms: a genuine primary research study you design and carry out yourself, or a research-based essay analyzing and evaluating existing psychological studies and theories. Choosing the right format for your specific research question — and designing it properly from the start — is the single biggest factor in how manageable this essay will be.
If you’re still narrowing down your topic, see our guide on writing a strong Extended Essay research question first.
Primary Research vs Research-Based Essay: Which Should You Choose?
Primary research (designing and running your own study) tends to score well when done carefully, because it demonstrates genuine methodological understanding and original data analysis. However, it also carries more risk — a flawed design can’t be fixed after data collection, and ethical approval processes take real time.
Research-based essays (critically analyzing and comparing existing studies and theories) are often the more manageable choice for most students, since they don’t require running your own data collection, but they still demand genuine critical evaluation rather than mere description of existing research — simply summarizing studies will not score well.
If You Choose Primary Research: Key Design Steps
- Define your variables precisely — a vague independent or dependent variable is one of the most common reasons Psychology EEs lose marks
- Choose an appropriate research design — experimental, correlational, or observational, depending on your specific research question
- Plan your sampling method and be explicit about its limitations (opportunity sampling, volunteer sampling)
- Address ethics thoroughly — informed consent, right to withdraw, debriefing, and confidentiality all need explicit treatment, not just a brief mention
- Choose your statistical test in advance — knowing which test you’ll use before collecting data ensures you gather the right type and amount of data
If You Choose a Research-Based Essay: Key Structural Steps
- Choose a genuinely debatable question — one where psychological research offers competing theories or conflicting findings, not a settled consensus
- Select 3-5 key studies or theories to analyze in depth, rather than superficially covering many
- Compare and evaluate, don’t just describe — examine methodological strengths and weaknesses, contradictory findings, and real-world applicability
- Build toward a genuine argument, using the studies as evidence for a position you take on your research question
Strong Research Question Examples
- Primary research: “What is the effect of background music genre on short-term memory recall accuracy among [specific participant group]?”
- Research-based: “To what extent does the cognitive approach provide a more convincing explanation for the development of phobias than the behaviorist approach?”
For more topic inspiration across other subjects, see our full list of 50 Extended Essay topic ideas by subject.
Common Mistakes in Psychology Extended Essays
- Choosing primary research without enough time to properly pilot the study and fix design flaws
- Vague or poorly operationalized variables that make replication or clear measurement impossible
- Superficial ethical discussion treated as a formality rather than a genuine consideration
- Research-based essays that summarize studies chronologically instead of building a comparative argument
Final Tip
Whichever format you choose, start by writing your research question as if it were a debate motion — something two well-informed psychologists could genuinely disagree about. This framing naturally pushes you toward the kind of analytical, evaluative essay that scores well.