In-depth interviews can be defined as a qualitative research technique which involves “conducting intensive individual interviews with a small number of respondents to explore their perspectives on a particular idea, program or situation” (Boyce and Neale, 2006, p.3).

Interviews can be divided into three categories: structured, semi-structured, and unstructured.

Structured interviews consist of a set of pre-determined questions that are asked from each interviewee in the same manner. Data collected by conducting structured interviews is perceived to be associated with high level of validity, due to the fact that each member of the sample group is asked the same questions, and therefore, there are fewer chances for the interviewee to be biased.

Semi-structured interviews include the elements of both, structured and unstructured interviews in a way that interviewer is sure about the areas the interviews need to cover and, interviews may have several ready questions that each interviewee is going to be asked. But, at the same time, additional unplanned questions might be asked during interviews in order to clarify some points stated by interviewees, or to clarify any other related points.

Unstructured interviews do not have any pre-determined specific direction and are usually conducted in an informal and conversational manner. There is a great potential for bias in part of interviewee, and therefore this type of interviews lack reliability from research perspectives. Unstructured interviews mainly take place in show business.


Advantages of interviews

Advantages of interviews are listed by Saunders et al (2007) as the possibility of obtaining comprehensively detailed primary data than can be immediately analysed.

Although, face-to-face interviews are expensive to conduct and can be very time-consuming, its advantages that include the possibility to control the flow of primary data collection process and the possibility to cover the project issues in an in-depth manner outweigh its disadvantages.


Disadvantages of Interviews

Listing the drawbacks of the survey method Proctor (2003, p.235) stresses the fact that the information obtained by interviewing is mainly based upon interviewees statements about their past experiences and their future plans.

Denscombe (2004, p.8) accepts the shortcomings of face-to-face interviews such as being expensive and time-consuming, however, convincingly argues, that the advantages of this method such as information being more detailed and rich, and the advantage of the possibility of immediately validating the data far outweighs it’s disadvantages.


Threats to Validity in Interviews

Kark and Jerome (1986, p.9) warn about five following points which threats the validity of the research the primary data for which is obtained through interviews.

The following three conditions of valid research interviews as specified by Hutchinson (2007) were met during dissertation interviews:

a)         Interviewer should have an open mind. Even if the interviewer does not agree with interviewee he/she should stay objective and should not display disagreement with the personal opinions of interviewees regarding the research questions.

b)         Interviewers should ask questions effectively. Any questions should be avoided that could lead interviewees to specific answers

c)         The timing and environment for the interview should be effective. Interviews should be conducted in relaxed environment, and interviewees should be free of any kind of pressure whatsoever.

Beiske (2007) warns that unstructured interviews are best suitable only to be used by experienced researchers, and advises inexperienced researchers, like the author of this proposal not to use them.

Respected scholars warn that “in conducting an interview the interviewer should attempt to create a friendly non-threatening atmosphere. Much as one does with a cover letter, the interviewer should give a brief, casual introduction to the study; stress the importance of the person’s participation; and assure anonymity, or at least confidentiality, when possible” (Connaway and Powell, 2010, p.170).

Moreover, Engel and Schutt (2009) warn about possible interviewee bias during the primary data collection process and argue that interviewee bias would seriously compromise the validity of the project findings. Other scholars, on the other hand, recommend that “some interviewer bias can be avoided by ensuring that the interviewer does not overreact to responses of the interviewee. Other steps that can be taken to help avoid or reduce interviewer bias include having the interviewer dress inconspicuously and appropriately for the environment, holding the interview in a private setting, and keeping the interview as informal as possible” (Connaway and Powell, 2010, p.172).



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