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A Level · Cambridge (CIE) · 9990

Choose self-reports, case studies and observations

Match questionnaires, interviews, case studies and observations to a research question and evaluate the evidence each can provide.

Section Paper 4 · Specialist Options: Application and Research Methods

Cambridge International AS & A Level Psychology 9990 · 2028–2030 · Version 1 · RM-SELF-REPORTS / RM-CASE-STUDIES / RM-OBSERVATIONS

Original StudyForA teaching mapped to the Cambridge 2028–2030 syllabus. These lessons are independent study support, not Cambridge material, official mark schemes or awarded grades. No lesson reproduces a research article or Cambridge question.

Before you begin

  • This pathway supports the 2028–2030 syllabus only. AS candidates take Papers 1 and 2; A Level candidates also study two of the four specialist options and take Papers 3 and 4. The separate 2027 syllabus is not mapped here.

Work on paper. Try each question before revealing help, and explain why your method works.

Quick readiness check

Which question format can let participants explain an unexpected experience in their own words?

What you will learn

  • Distinguish self-report formats and techniques
  • Explain the single-unit depth of a case study
  • Classify observation choices
  • Apply method strengths and limits to new scenarios

Self-reports ask participants to describe their own experiences

A questionnaire can use paper-and-pencil or online delivery and open or closed questions. Closed answers are easier to compare, but can restrict responses; open answers can reveal detail, but are harder to code consistently. An interview can be structured, semi-structured or unstructured and can use telephone or face-to-face contact. More flexibility can clarify meaning, but interviewer behaviour and social desirability can influence answers.

Choose wording that is neutral, understandable and focused on one idea. A leading question suggests a preferred answer; a double question asks about two things at once. The format should match the data needed, the participants and the ethical safeguards.

A case study provides detailed evidence about one unit

A case study investigates one participant or unit in depth. It can combine interviews, observations, records and tests, allowing a detailed account of a rare or complex case. The depth may not generalise to other people, and evidence from multiple sources still needs careful checking. A case study is a method, not simply any interview.

Observation choices describe how behaviour is recorded

An observation may be overt or covert; participant or non-participant; structured or unstructured; naturalistic or controlled. These are separate choices. A structured observation uses defined behaviour categories and a recording scheme; an unstructured observation records behaviour more openly. Operationalised categories and observer training can improve consistency, while narrow categories may miss context.

Covert observation may reduce participants changing behaviour because they know they are observed, but it raises consent and privacy concerns. Naturalistic settings show behaviour in context but are harder to control. Apply ethics and validity to the actual setting rather than assuming one observation type is always best.

Sources for this lesson

Pause and explain

A researcher records every time a defined behaviour occurs using a prepared checklist. What is the key observation feature?

Put the idea to work

Worked example

A researcher wants detailed accounts of how one athlete adjusts to an unusual training injury. Which method fits and what is one limit?

Show the worked solution
  1. The question concerns one person and a complex process over time.
  2. A case study can combine interviews, observations and records for detailed understanding.
  3. The depth of one case does not establish that the same pattern applies to other athletes.

Answer A case study is suitable for detailed, multi-source evidence about the athlete; its findings may have limited generalisability.

Try a topic test

Choose Easy, Normal or Difficult. Save your answers and open worked review after finishing.

Test this topic →

From guided practice to a new situation

Write your answer and reasoning first. Use a hint only if you are stuck. The model solution is for self-checking; your written work is not automatically marked.

1 · Guided

A survey asks, ‘How helpful and friendly was the tutor?’ Explain one problem and improve the item.

Give me a hint

It asks about two qualities in one question.

Compare my reasoning
  1. A participant might find the tutor helpful but not friendly.
  2. The double question does not show which quality a rating refers to.
  3. Separate it into two neutral items, one about helpfulness and one about friendliness.

It is double-barrelled; ask two separate, neutrally worded questions.

Look for these in your work

  • Problem identified
  • Ambiguity explained
  • Practical rewrite proposed
2 · Independent

A researcher watches children during a group puzzle without joining in and records each turn using pre-set categories. Classify two observation choices.

Give me a hint

Use the observer’s role and the recording scheme.

Compare my reasoning
  1. The researcher is non-participant because they do not join the group.
  2. The observation is structured because categories are set before recording.
  3. The setting alone does not tell us whether it is naturalistic or controlled.

Non-participant and structured; the setting must be described separately to classify naturalistic versus controlled.

Look for these in your work

  • Role classified
  • Structure classified
  • Does not infer an unstated setting
3 · Transfer

A researcher wants to understand why a single commuter avoids a crowded station. Compare a case study with a closed questionnaire for this question.

Give me a hint

The question asks for an explanation of one person’s behaviour.

Compare my reasoning
  1. A case study can combine detailed interview, observation and travel records to explore context.
  2. A closed questionnaire is quicker to compare but limits the participant to supplied choices.
  3. The case study is richer for this one case, but it cannot by itself support broad generalisation.

A case study better fits the depth of the single-person question; a closed questionnaire is more standardised but may miss the person’s reasons. The one case still has limited generalisability.

Look for these in your work

  • Both methods compared
  • Context and response detail considered
  • Generalisability limitation stated

Common mistakes

  • Treating all interviews as structured or all questionnaires as closed questions.
  • Assuming a large number of self-report responses removes social-desirability bias.
  • Calling an observation ‘structured’ only because it happens in a laboratory.
  • Generalising from one case without evidence that other cases are comparable.
Recall without your notes

What can you explain now?

What distinguishes a case study from a survey of many people?

Compare with the explanation

A case study examines one participant or unit in detail.

It often combines sources for depth; the number of sources does not change the single-unit focus.

After trying it yourself, choose your next review. This is your self-assessment.

Your review choice appears on Today. Sign in to sync it across devices.

Make it stick

How do self-reports, case studies and observations differ in the evidence they collect and the limits they introduce?

If you needed the solution, close it and solve the problem again from a blank page. A correct answer is stronger when you can explain the reason for each step.

Keep learning Psychology

Course scope and assessment

Seven original lessons map all 15 AS research-method and methodological-concept sections to explained Guided, Independent and Transfer practice. All 12 compulsory AS core studies have original study-specific teaching and staged practice; five additional A Level methodology lessons cover research design and validity. All 15 Clinical, all 15 Consumer (2.1.1–2.5.3) and all 15 Health (3.1.1–3.5.3) Psychology sections link to original teaching and staged practice. All 15 Organisational Psychology sections 4.1–4.5 now have original teaching and explained staged practice; the six new 4.4–4.5 lessons bring the planning map to 92 of 92 indexed sections. Consumer lessons cover physical and psychological environments; decision models, heuristics and mistakes; packaging, selling and buying; advertising, self-monitoring, product placement, brand recognition and slogans. Evaluation boundaries are explicit: studies use particular products, samples, tasks and settings; gaze, recall, self-report, EEG indices, ratings, choices and purchases are different outcomes. Health evidence is bounded: Laba et al. measured hypothetical preferences; Riekert and Drotar raise a non-response concern; Chung and Naya's cap tracked openings, not swallowing; Chaney et al. was a short caregiver-reported pilot; Yokley and Glenwick examined immunisation attendance in one public-health setting. MacLachlan et al. report one patient, not a controlled treatment effect; Brudvik et al. compared separate child, parent and physician ratings in one emergency department. Chandola et al. found a cohort association; Wang et al. measured responses during a monitored arithmetic task; Evans and Wener observed commuters; Bridge et al. found mixed self-rated outcomes in radiotherapy. Janis and Feshbach measured short-term self-reports in one school; Lewin et al. tested a rehabilitation package, not information alone. Tapper et al. and Fox et al. studied bounded school and worksite programmes; incentive effects do not establish transfer or rule out reporting effects. Weinstein measured comparative expectations, while Seligman’s framework is conceptual and Shoshani and Steinmetz used a school-level comparison. These findings do not establish universal health effects or diagnose individuals. Need-theory examples use a child measurement study, not a workplace test; SMART is a practical checklist, not a motivational theory. Landry et al. compared reward framing with student volunteers in a lab; this does not establish universal effects in workplaces. Cuadrado et al. (2008) measured undergraduate evaluations of presented leaders, not workplace performance or hiring; this does not establish a universal gender effect. The historical 1995 Munchausen criteria are not a current diagnostic checklist. Cambridge’s 2028–2030 Reference List treats Oruč et al. (1997) as an example of genetic explanation although its participants had bipolar I; gambling disorder is listed in Cambridge’s Clinical topic but classified under addictive behaviours in ICD-11. Candidates choose two options, but all four remain listed so schools can select a route. The 92-section count is a planning index, not a Cambridge score. Remaining work is deeper coverage review, separate-year syllabus reconciliation, timed-paper practice and human subject-expert review. The separate 2027 and 2024–2026 syllabuses are not reconciled into this route. Practice is not official grading, a timed-paper simulation or human subject-expert review.

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