Structured interviews are ones which have a pre-ready set of standardised questions (often closed) which the interviewer must keep to; the interviewer asks all the interviewees the same set of questions.
Semi-structured interviews are which have a pre-ready set of standardised (both open and closed) but the interviewer has the ability to ask the interviewee to elaborate on any answers given.
Unstructured interviews are in which the interviewer does not have any pre-ready set of standardised questions and the interviewer can ask any questions which are relevant to the topic; this type of interview is often in-depth.
They are seen as one of the most efficient types of research method as they are very cheap as few resources are need.
Certain personal skills and characteristics may be needed by the interviewer; these included the ability to establish rapport.
In some cases, such as those which aim to investigate sensitive issues, interviews…