Types of Interviews
Questionnaire design will vary significantly depending upon the type of interview you conduct. It is possible to combine elements of these three approaches in a single interview or project (from most-structured to least structured).
This type of interview is sometimes called a standardized interview. It is generally scripted in full, including opening and closing comments and all questions and probes (defined below). The goal is to always ask the questions the same way, in the same sequence, across all participants. There is no flexibility in the wording or order of questions. Responses are open-ended.
This type of interview is sometimes called the interview guide approach. The interviewer can vary the wording and order of the questions; there is an outline of topics or issues to be covered (referred to as an interview guide). This approach is used by researchers to ensure that all relevant issues are discussed with each participant, while leaving the interviewer free to pursue unanticipated topics that may arise during the interview. With this approach, the researcher can vary the wording and order of the questions, or even use a list of general topic areas in place of scripted questions, forming the questions more spontaneously within each topic during the interview. This allows the interviewer to build a conversation around a topic and to vary subsequent questions according to participants’ responses. The interviewer is also able to pursue unanticipated topics that may arise during the interview.
This type of interview is also called an informal conversational interview. No pre-determined set of questions or script is used; questions emerge in the course of field work. The idea is to gather data from conversations that may be quite different from participant to participant. This approach works best when the researcher is present within the program setting and interacting with program participants in an ongoing fashion. Individual participants may be interviewed more than once, and interview questions tend to change over the course of a study, as new information emerges.
Probes are (often pre-planned) follow-up questions that can be used in any interview approach to elicit better, deeper, or more complete responses from participants. It is common and helpful when drafting interview questionnaires to develop probes to accompany specific questions or topics to draw out more details from interviewees.
For the structured approach, probes would be fully developed as part of the interview instrument and asked in the same way in the same order with each participant. In the semi-structured interview probes might be a simple list of topics to remind the interviewer to get more details if an open-ended response does not address something important.
Example of a question with probes (structured interview approach):
Open-ended Question: How has pest management in your school district changed as a result of the policy?
- Could you give some examples of what you do differently?
- How does it compare to the previous program in terms of pest problems, pesticide use, and cost?