self-report techniques

open questions

qualitative data

open questions strengths

rich, detailed data, unexpected answers possible.

open questions limitations

difficult to analyse statistically (thematic analysis needed), time‑consuming, participant may write little

closed questions

quantitative data

closed questions strengths

easy to analyse, replicate, and compare; quick

closed questions limitation

forces simplistic answers, may lack depth, can lead to frustration.

Questionnaire construction principles

• Avoid leading questions (“Don’t you agree that…”).

• Avoid double‑barrelled questions (“Do you like A and B?”).

• Use clear, simple language (no jargon).

• Pilot study to check for ambiguity.

• Consider order effects (fatigue, boredom).

• Ensure anonymity to reduce social desirability bias.

Structured description

Pre‑set questions, read aloud in same order

unstructured description

Guided conversation, no fixed questions

Semi‑structured description

Some pre‑set questions plus follow‑up probes

structured evaluation

Easy to replicate (high reliability), less interviewer bias; but no flexibility, may miss important detail

unstructured evaluation

Rich, flexible data (high validity), can follow up on answers; hard to analyse, high interviewer bias, time‑consuming

semi-structured evaluation

Balance of reliability and depth; but still time‑consuming, requires skilled interviewer

social desirability bias

participants give answers they think are socially acceptable. Reduce by ensuring anonymity, using neutral wording, and establishing rapport.