Here are some basic interviewing guidelines you may want to consider when collecting data through interviews. These are the primary data sources for qualitative methods including: case study, ethnography, grounded theory, narrative research, and phenomenology.

Inclusion-Exclusion Criteria  Ask qualifying questions in order to validate that potential interviewees meet your inclusion-exclusion criteria, which is defined as “in clinical research, criteria used for determining which individuals are eligible to participate in a particular study” (VandenBos 2007) and that they are willing to participate voluntarily. These individuals would be those, who have experienced the phenomenon, issue, or problem you are studying.

Ask qualifying questions in order to validate that potential interviewees meet your inclusion criteria and that they are willing and able to participate voluntarily. When some individuals find out that a study is about to commence, they may immediately volunteer. If they know you, they may insist on being included. You must resist the desire to please them, if they do not meet the criteria for the study. In fact if they know you, that would be an excellent reason to exclude them – potential conflict of interest.

Purpose of the Interview

You want to be clear on the purpose of the interview and convey that message to the potential interviewees. It should be in alignment with your Purpose of the Study statement and clearly stated in the Informed Consent form.

Expectations of Participants

Let potential interviewees know what you expect of them in order to participate in the study. In other words, explain the nature or subject of the interview. Triangulation is now considered standard practice when collecting interview data. Schwandt (2007), when defining triangulation, states: “This is a procedure used to establish the fact that the criterion of validity has been met.” You will want to remind them that in addition to the actual interview they will be asked to review, approve, and return their transcript of the interview to you. This is called member check or validation (Vogt 2005).

Time Commitment

Let potential interviewees know the approximate duration time for the interview. Less that 60 minutes is best. After that amount of time, most people start to feel fatigue and the quality of their responses may deteriorate. So you want to avoid letting this happen. If more time is needed, you can schedule a follow-up session.

Right to Resign

Clearly make the point to potential participants and also to those who quality, that they may discontinue and withdraw from the interview at any time. This should be stated in your Informed Consent form. Occasionally, for unknown reasons individuals lose interest in the interview, but they are reluctant to quit or resign. Many times they will give you ultra-short responses and/or very vague answers. If you are convinced, that the interviewee is just going through the motions and is totally uninterested in genuine participation, you may want to make some excuse and politely terminate the interview.


Tell potential interviewees that their identity is confidential and that you will be the only one who will know their name. It is good to explain to them that you will assign a fictitious name and an alphanumeric code to their interview recording and transcript.

Interview Questions

Have a list of predetermined open-ended questions. These are interview questions, which form the foundation of the interviews. These should be the same ones that have been approved in your Proposal and Institutional Review Board application.

What Not To Do

Avoid “leading” the interviewees. If you make a positive or negative comment about what the interviewee has stated, this is a form of leading. This behavior will distort their responses and contribute to invalid interviews.

When to Interrupt

Only interrupt interviewees to ask for clarification, additional details or information, and/or to request stories. If interviewees give you incomplete or vague responses, it is appropriate to ask for more information. You could say: Can you tell me more about that? When you say “___________,” what do you mean? You need to get their story, their perceptions, and experiences. You want their thick descriptions.

After The Formal Questioning

When all predetermined questions have been asked, you can always ask whether there is additional information the interviewees would like to share that had not previously been addressed.

Acknowledge Your Appreciation

At the end of the interview, offer a sincere “thank you.” Within a day or two, it is always polite and first-class to send each interviewee a written thank you note. Your study required their participation so your note of thanks reinforces your appreciation.

For additional reading and references, you may want to consult:

Schwandt, T.A. (2007). The Sage Dictionary of Qualitative Inquiry,         (3rd ed.). Los Angeles: Sage Publications.

Seidman, I.E. (1998). Interviewing as Qualitative Research: A Guide       for Researchers in Education and the Social Sciences. (2nd ed.).  New York: Teachers College Press.

VandenBos, G.R. (2007). APA Dictionary of Psychology. (Ed).             Washington, DC: American Psychological Association.

Vogt, W.P. (2005). Dictionary of Statistics & Methodology: A           Nontechnical Guide for the Social Sciences. (3rd ed.). Thousand Oaks, CA: Sage Publications.

Recommended citation for this article:

Wargo, W.G. (2016). Interviewing Guidelines for Dissertation and           Thesis Writers. Menifee, CA: Academic Information Center.

For more information, please contact William Wargo, Ph.D. at or (951) 301-5557.  ©2016