DPI(7) QUESTIONNAIRES AND INTERVIEWS.
Questionnaires: Keep questions and instructions easy to understand, avoid leading questions, keep the information minimal and relevant, being mindful of ethics and conduct a pilot study.
Interviews: Same as questionnaires but conducted face to face, the questions are pre-determined for constructed interviews,
Validity: Affected by a biased sample (social desirability) to increase test face and concurrent validity.
Reliability: Affected by interviewer bias, to increase this test inter-rater reliability, if two interviewers produce the same outcome.