Research methods is the engine room of A Level Psychology. It’s where you learn how psychologists design studies, collect and analyse data, and decide what the results actually mean. AQA assesses these skills across the whole course (with a substantial section in Paper 2), so confident research-methods knowledge is a major marks-earner.

You’ll use maths at roughly GCSE/Level 2 to handle data, select appropriate tests, and interpret outputs. For the official coverage and assessment objectives, see the AQA A Level Psychology (7182) specification.

Core building blocks

• Aims & hypotheses: directional vs. non-directional; operationalising variables.
• Variables: IV, DV, control variables; extraneous vs. confounding variables.
• Experimental designs: independent groups, repeated measures, matched pairs.
• Non-experimental methods: observations, self-reports (questionnaires/interviews), correlations, case studies, content analysis.
• Sampling: random, stratified, systematic, opportunity, volunteer; population vs. sample; sampling bias.
• Ethics: consent, deception, debrief, right to withdraw, confidentiality, protection; BPS guidelines.

Data, measurement & display

• Data types: quantitative vs. qualitative; primary vs. secondary.
• Levels of measurement: nominal, ordinal, interval.
• Descriptive statistics: mean/median/mode; range & standard deviation; percentages & ratios.
• Graphs & tables: bar charts, line graphs, histograms, scattergrams; when to use which; spotting patterns/anomalies.

Inferential testing — choosing & interpreting

You need to recognise when to use a test and interpret significance using critical values (no heavy formulas). Think in three steps:

1. Test type: difference or correlation?
2. Design/relationship: related (repeated/matched) or unrelated (independent groups)?
3. Measurement level: nominal, ordinal or interval?

Typical AQA tests you should know conceptually:

• Sign test (simple difference, nominal)
• Wilcoxon signed-rank & Mann–Whitney U
• Spearman’s rho & Pearson’s r
• Chi-squared (χ²)
• t-tests (related & unrelated)

Also understand p-values, Type I/II errors, and what a “significant” result allows you to conclude (and what it doesn’t).

Reliability, validity & control

• Reliability: internal (split-half) vs. external (test–retest); inter-observer reliability.
• Validity: internal, external (ecological, temporal, population), concurrent, face, construct.
• Controls: counterbalancing, random allocation, single/double blind, standardisation.

Designing & evaluating studies

• Write clear procedures and materials; pilot studies to refine measures.
• Identify strengths/limitations (control, realism, ethics, generalisability).
• Improvements: better sampling, tighter controls, alternative measures/settings.

Exam strategy (quick wins)

• Always define then apply: 1–2 line definition, then link to the vignette.
• Show the three-step test choice: study type → design/relationship → measurement level → test name.
• Explain significance in words: “At p ≤ 0.05, result is significant; reject/accept H₀; conclude …”
• Use mini-checklists for reliability/validity and ethics to structure 6–12 mark answers.

Frequently Asked Questions

Is research methods only in Paper 2?

No—AQA assesses research methods across the course, with a substantial section in Paper 2 and applications in other papers.

Do I need advanced maths?

No. The maths is around GCSE/Level 2: stats, graphs, choosing tests, and interpreting significance.

What’s the fastest way to improve?

Drill test selection with short scenarios, practise interpreting critical values tables, and write concise reliability/validity evaluations linked to the study.

Ready to start A Level Psychology?