There is a range of considerable bias due to the understanding by the users of the questions, and the subjective collected information might be misleading or inaccurate. The critical aspects are the choice of the place for the interview and how to conduct it. The investigator does not impose a questionnaire and must follow the thoughts and reactions of the respondent. This type of interview is mostly applicable in situations where both qualitative and quantitative feedback are required. Structured interview Structured interviews are useful in situations where the respondents range of replies may be estimated and there is a need to clarify details, opinions or ideas.
Structured interviews work well when the assessment goals are clear.