3.1.2 Individual interviews

Wendy.Christiaens        What are individual semi-structured interviews?

Interviews are used in many contexts (journalism, human resource managers, etc.) and for many purposes (entertainment, recruitment of personnel, etc.), hence scientific data collection is only one very specific application, which should not be confused with other applications. The interview is easily trivialized as it is common practice in the media landscape which surrounds us. Fontana and Frey even speak about “the interview society” according to Atkinson and Silverman. Practicing health professionals routinely interview patients during their clinical work, and they may wonder whether simply talking to people constitutes a legitimate form of research (DiCicco-Bloom et al,2006). In qualitative research, however, interviewing is a well established research technique and two types can be distinguished: semi-structured and unstructured. Structured interviews are out of scope here, because they consist of administering structured questionnaires producing quantitative data.

Unstructured interviews are more or less equivalent to guided conversations(DiCicco-Bloom et al,2006). Originally they were part of ethnographers’ field work, consisting of participant observation and interviewing key informants on an ongoing basis to elicit information about the meaning of observed behaviors, interactions, or artifacts (DiCicco-Bloom et al,2006). There is no list of questions, nor an interview guide, the questions asked are based on the responses of the interviewee, as in the natural flow of a conversation (Britten, 1995).

Semi-structured interviews are often the sole data source in a qualitative research project. A set of predetermined open-ended questions is used to guide the interview, but other questions emerging from the dialogue can be added (Britten, 1995). Also the iterative nature of the research process in which preliminary data analysis coincides with data collection, results in altering questions as the research process proceeds. Even so, questions that are not effective in eliciting the necessary information can be dropped or replaced by new ones (Britten, 1995).

Essentially an interview consists of someone who asks questions (interviewer), someone who answers these questions (interviewee) and the registration of those answers in some way (Mortelmans, 2009).

The interview as qualitative research method differentiates from other forms of interviewing used in varied domains. Mortelmans pays attention to four characteristics:

  • Flexibility; with flexibility internal and external flexibility is meant: external refers to the iterative use of interviewing and data analysis. Structure and content of the subsequent interview may be changed in function of the analysis of the previous one. Internal flexibility points to the fact that the sequence of the prepared interview questions and themes should stands in function of the interviewee in order to guard the natural flow of the conversation.
  • The interviewee leads so to speak the conversation. The interviewer only guards the scope of the conversation and makes sure that all the topics are covered.
  • Non-directiveness; the interviewee steers the interview and the interviewer only makes sure that the conversation does not stray too far by means of non-directive interview techniques.
  • Direct face-to-face contact is important to built trust and get in-depth information, but this depends on the topic and should be considered case by case.        When to use individual semi-structured interviews?

Individual semi-structured interviews are useful to:

  • Collect data on individuals’ personal histories, perspectives, and experiences, particularly when sensitive topics are being explored (Mack, 2005).
  • Elicit a vivid picture of the participant’s perspective (Mack, 2005).
  • Provide context to other data, offering a more complete picture (Boyce et al, 2006)
  • Learn about the perspectives of individuals, as opposed to, for example, group norms of a community, for which focus groups are more appropriate (Mack, 2005).
  • Get people to talk about their personal feelings, opinions, and experiences (Mack, 2005).
  • Gain insight into how people interpret and order the world on the research topic (Mack, 2005).
  • Address sensitive topics that people might be reluctant to discuss in a group setting (Mack, 2005).
  • Elicit information from key informants (Sofaer, 1999).
  • Examine people’s experiences, attitudes and beliefs (Huston et al, 1998).        Strengths and weaknesses of the method


  • They provide much more detailed information than what is available through other data collection methods, such as surveys (Boyce et al, 2006).
  • Questions can be prepared ahead of time. This allows the interviewer to be prepared and appear competent during the interview (Cohen, 2008).
  • Semi-structured interviews also allow informants the freedom to express their views in their own terms (Cohen, 2008).
  • Semi-structured interviews can provide reliable, comparable qualitative data (Cohen, 2008).


  • Interviews can be time-intensive because of the time it takes to recruit participants, conduct interviews, transcribe them, and analyse the results. In planning your data collection effort, care must be taken to include time for transcription and analysis of this detailed data (Boyce et al, 2006).
  • Interviewers must be appropriately trained in interviewing techniques. To provide the most detailed and rich data from an interviewee, the interviewer must make that person comfortable and appear interested in what they are saying. They must also be sure to use effective interview techniques, such as avoiding yes/no and leading questions, using appropriate body language, and keeping their personal opinions in check (Boyce et al, 2006)
  • Data from individual semi-structured interviews are not generalizable in a statistical way, but they are theoretically transferrable, because small samples are chosen and no random sampling methods are used. Individual semi-structured interviews however, provide valuable information, particularly when supplementing other methods of data collection. It should be noted that the general rule on sample size for interviews is that when the same stories, themes, issues, and topics are emerging from the interviewees, then a sufficient sample size has been reached (Boyce et al, 2006).        How to plan the research design?

See  “How to plan the research design?        Modalities of data collection

Individual semi-structured interviews are usually conducted face-to-face and involve one interviewer and one participant. Phone conversations and interviews with more than one participant also qualify as semi-structured interviews, but, in this chapter, we focus on individual, face-to-face interviews (Mack, 2005).        Data collection tools

The data collection tools to carry out interviews are topic lists, questionnaires and field notes. Topic lists and questionnaires are described here.

Researchers use field notes to record observations and fragments of speech. Field notes should be written up as soon as possible after the events to which they refer. If possible, short “aide-mémoire” or pocket dictaphones may be used in fieldwork settings, to facilitate later expansion of the notes into proper fieldnotes (Bloor et al, 2006). In the chapter on observational techniques field notes are addressed in more detail (here).        Sampling

For general issues on sampling, see  “Sampling issues in qualitative research: who and how many?”.        Human resources necessary

In the ideal scenario researchers plan, organize, carry out and transcribe the interviews themselves, to be completely immersed in the data, but in practice the interviews are often carried out by subcontractors and the transcriptions are often done by professional typists.        Practical aspects

Preparations for the interview see “How to run the data collection” .

Physical organisation of an interview. Take the following rules into account:

  1. Interviewee and interviewer should not sit opposite each other, but rather at an angle of 90° or less.
  2. The interview should take place in a quiet place where the interviewee feels at ease.
  3. Avoid the presence of third parties.      Analysis and reporting of findings

See "How to prepare data for analysis",  “How to analyse?” and  “How to report qualitative research findings?” .      Examples of KCE reports using the method

[1]           We propose a example of a ‘standard introductive text’ in appendix.