Questionnaires and interviews

Questionnaires

A questionnaire is a written set of questions answered by the participant.

• Closed questions give fixed answers (yes/no, tick boxes). They give quantitative data that are quick to analyse and compare, but may force answers that do not fit.
• Ranked scale questions ask people to rate on a scale, for example a Likert scale from strongly agree to strongly disagree. They give ordinal data.
• Open questions let people answer in their own words. They give qualitative data that are rich and detailed but harder to analyse and compare.

Design tips: run a pilot study; avoid leading, emotive or double questions; use clear, jargon-free language; put sensitive questions later; give standardised instructions; include the right to withdraw and confidentiality.

Interviews

• Structured: a fixed list of questions asked in the same order; easy to compare and replicate, but cannot follow up interesting answers.
• Semi-structured: set questions plus follow-up questions; a balance of comparability and depth.
• Unstructured: topics rather than set questions, like a conversation; rich, detailed data and good for sensitive issues, but hard to compare, time-consuming and needs trained interviewers.

Researcher effects and other problems

• Researcher (interviewer) effects: the researcher's age, gender, tone, expectations or body language influence the answers. Standardised wording and training reduce this.
• Social desirability bias: people give answers that make them look good, not true answers. Anonymity helps.
• Demand characteristics: participants guess the aim and change their answers.
• Questionnaires are cheap and reach many people, but return rates can be low and those who reply may not be representative.

Worked example

A researcher asks 'Most people obey their parents, don't you agree?' Identify the problem and rewrite the question.

1. It is a leading question: it suggests the expected answer.
2. Rewrite as a neutral ranked scale item: 'I obey my parents' with Strongly agree / Agree / Don't know / Disagree / Strongly disagree.

Answer: It is leading; use a neutral Likert item such as 'I obey my parents' rated from strongly agree to strongly disagree.

Check yourself

1. 'Rate how far you agree: I would obey a police officer (strongly agree to strongly disagree).' What type of question is this?
   • A ranked scale (Likert-type) question
   • An open question
   • An unstructured interview question
   • A secondary data question
   Show answer

   A ranked scale (Likert-type) question. It asks for a rating on a fixed scale.

2. Which interview type uses set questions but allows follow-up questions?
   • Structured
   • Unstructured
   • Semi-structured
   • Closed
   Show answer

   Semi-structured. Semi-structured combines a schedule with flexibility.

3. What is the main advantage of open questions?
   • They give rich, detailed qualitative data in the participant's own words
   • They are quick to turn into percentages
   • They prevent social desirability bias
   • They make answers easy to compare
   Show answer

   They give rich, detailed qualitative data in the participant's own words. Open questions allow depth and new ideas.

4. An interviewer smiles and nods when participants give the answer she expects. This is an example of
   • secondary data
   • random sampling
   • a ranked scale
   • a researcher effect
   Show answer

   a researcher effect. Her behaviour may shape the answers.

5. Why would a researcher run a pilot study of a questionnaire?
   • To increase the sample size of the main study
   • To check that questions are clear and not leading before the main study
   • To collect secondary data
   • To make the study unethical
   Show answer

   To check that questions are clear and not leading before the main study. A small trial run finds problems in wording and length.

6. Explain how social desirability bias could affect a questionnaire about obedience.
   Show answer

   Participants may give answers that make them look good, such as saying they would refuse unjust orders, rather than what they would really do, so the data lack validity.. People present themselves well, so answers may not match real behaviour.

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Sources

• Pearson Edexcel International Advanced Subsidiary/Advanced Level in Psychology specification (issue January 2026)
• Pearson International A Level Psychology component guide: WPS01
• IAL Psychology revision site: Self-reports

Last updated 8 November 2026. Spotted a mistake? Tell us.