Interviews consist of data gathering through direct interaction between a researcher and respondent where answers to questions are gathered verbally. They can take the form of face-to-face encounters, the telephone or the web. Although usually conducted on a one-to-one basis, they can be carried out with a group of individuals in the form of a focus group. These are small groups of individuals who are facilitated by the researcher to discuss certain topics and experiences.

Interviews are one form of data collection that is used in both quantitative and qualitative studies, and have the ability to describe, explain and explore issues from the individual or ‘insider’ perspective (Tod 2010). The research approach will influence the type of data collected and method of data analysis. One important advantage of interviews over other methods of data collection is the higher response rate than with other methods (Burns and Grove 2009). In qualitative research, they have become the most common type of method of data collection (Holloway and Wheeler 2010). However, from the researcher’s perspective, they present some of the greatest challengers and the need for a high level of skills in their use. To a large extent, the researcher becomes the tool of data collection in studies using this method. This is because, although interviews may be recorded in writing on a printed form or in a notebook, or verbally on audio equipment and later transcribed, it is the researcher’s skills and personality that will encourage or discourage the interviewee to open up and select the information they feel willing to disclose. During interviews, it is also the researcher’s ability to know when to seek clarification or illustration that can make all the difference to the quality of the data collected.

Interviews can be categorised by the degree of structure they contain. This can range from a highly structured format of questioning, where they virtually take the form of reading out questions from a questionnaire and recording the answers. This approach is used in survey designs that concentrate on the production of quantitative data. Here, the list of questions is not called a questionnaire but an interview schedule (Jackson et al. 2008). The advantages of this format, according to Bryman (2008), include the standardisation in the way questions are asked and recorded. This increases the accuracy of the results and also makes analysis easier and more compatible with statistical computer analysis programmes. The disadvantage of a highly structured approach is that there is little scope for spontaneity and depth of information. This can result in them being somewhat superficial, leaving us with little understanding of a situation. We must also remember that, as a self-report method, we have to assume that what someone states in an interview is accurate.

At the other end of the interview structure continuum is the unstructured or non-standardised interview where questions develop as appropriate with a participant. This allows situations to be seen through the eyes of those involved, a point made by Polit and Beck (2008: 392):

This means that rather than choose from what the researcher has decided are relevant options, the respondent can put what they see as important in their own words, so we get an insider’s description of events and issues. Such interviews have only a small number of prepared questions, called an interview guide; the rest will be requests for more detail or illustration. Often, they may start with a trigger question or grand tour question (Polit and Beck 2008), such as, ‘So what happened once you went into labour?’ The disadvantage of the approach is that it requires a great deal of personal skill from the researcher and generates a large amount of data to be analysed and coded, and so can be very time consuming and costly.

Somewhere between these two extremes are semi-structured interviews, which are a mixture of the two. They contain some standard questions covering issues or topic areas that are asked of everyone (Holloway and Wheeler 2010), but there is also the flexibility to probe and explore areas that seem appropriate to the individual concerned. The semi-structured approach ensures that important areas are covered with everyone, but still allows other areas to arise spontaneously.

Why choose interviews as a data collection method? There are a number of very clear advantages to using interviews, as can be seen from Box 10.1. According to Polit and Beck (2008: 424), these strengths far outweigh those of questionnaires. They are suitable for a wider variety of individuals than questionnaires, are less likely to lead to misinterpretations of the questions, and provide richer data. The presence of the interviewer can also be an asset as they can clarify questions and answers and gently probe where more information may be needed to gain a complete and accurate answer. This has been recognised by Burns and Grove (2009: 405), who suggest that interviews allow the researcher to explore a greater depth of meaning than can be obtained with other methods.