structured interviews
the second main categorizing principle of interviews is the degree of structure in them, with one extreme being the 'structured interviews'.In this format,the researcher follows a pre-prepared,elaborate 'interview schedule/guide',which contains a list of questions to be covered closely with every interviewee,and the elicited information shares many of the advantages and disadvantages of questionnaire data.Such tightly controlled interviews ensure that the interviewee focuses on the target topic area and that the interview covers a well-defined domain,which makes the answers comparable across different respondents.The other side of the coin is,however,that in a structured interview there is generally little room for variation or spontaneity in the responses because the interviewer is to record the responses according to a coding scheme. There is also very little flexibility in the way questions are asked because by adopting a standardized format it is hoped that nothing will be left to chance. This interview type is appropriate when the researcher is aware of what he/she does not know and can frame questions that will yield the needed answers.That is,structured interviews are used in situations where a written questionnaire would in theory be adequate except that for some reason the written format is not feasible.
Unstructured interviews
The other extreme, the 'unstructured interview'(sometime also referred to as the 'ethnographic interview'),allows maximum flexibility to follow the interviewee in unpredictable directions, with only minimal interference from the research agenda. The intention is to create a create a relaxed atmosphere in which the respondent may reveal more than he/she would in formal contexts,with the interviewer assuming a listening role. No detailed interview guide is prepared in advance,although the researcher usually thinks of a few opening questions to elicit the interviewee'story.During the interview,the researcher may ask an occasional question for clarification and may give reinforcement feedback as any good communication partner would to keep the interview moving,but interruptions are kept to a minimum.