Interviewing techniques

Introduction

A very commonly used method of data collection in the health sciences is interviewing. An interview can be thought of as a dialogue or conversation between the interviewer and the research participant with the purpose of eliciting information from the participant. Interviews are a key tool for the clinician and the health researcher as a means of collecting information about the opinions and experiences of patients and research participants. Interviews vary substantially in their structure, content and the way in which they are conducted. This chapter is concerned with the design and conduct of interviews and the analysis of interview data.

The aims of this chapter are to:

1. Distinguish between structured and unstructured interviews.

2. Outline commonly used strategies for conducting interviews.

3. Compare and contrast quantitative and qualitative strategies for conducting interviews.

Interviewing models

Many researchers distinguish between structured and unstructured interviews. Sometimes the terms ‘formal’ and ‘informal’ or ‘guided’ and ‘open-ended’ are also used (see, for example, Morse & Field 2003).

Denzin & Lincoln (2011) distinguished between three forms of interviews: (i) the schedule standardized interview in which the wording and order of all questions are exactly the same for every respondent; (ii) the non-schedule standardized interview where certain types of information are desired from all respondents but the particular phrasing of questions and their order are redefined; and (iii) the non-standardized interview in which no prescribed set of questions is employed.

If one defines an interview as a conversation, then a schedule-standardized interview is a very rigid form of conversation, almost like a play with a fixed script. In its most structured form, a structured interview may involve the reading of a prepared questionnaire to respondents and then filling in an answer form or response sheet for them on the basis of their answers. The questions are provided in a systematic order, with minimal or no deviation from the prepared script. In a structured interview, the role of the interviewer is to ask the questions and the role of the respondent is to provide the answers with minimal extraneous information. Conversely, an unstructured interview may involve the interviewer in asking no direct questions, but simply prompting respondents to reflect on their current interests and concerns. Clearly, between these extremes lie a variety of different types of interview strategies and degrees of structure. The three different approaches to conducting interviews can be seen as being on a continuum: (i) structured, (ii) semi-structured, and (iii) unstructured. Semi-structured and unstructured interviews may include in-depth approaches designed to elicit more detailed and personal information from participants (Minichiello et al 2008). The extent of ‘structure’ or ‘formality’ is determined by a number of factors, including the following:

1. Whether there is a fixed set of questions or schedule. In a structured interview, the interviewer has a pre-planned set of questions or schedule. These questions may or may not be presented in a fixed order. In an unstructured interview, there may be particular ‘themes’ to be explored without a specific order required or specific question wordings.

2. The way in which the information is recorded. There are a number of ways in which interview information may be recorded. Structured interviews tend to employ pre-planned answer sheets or response schedules. Unstructured interviews have less expectations and restrictions on the answer formats of the respondents. The interviewer may record the interview or take free-form notes.

3. The types of questions. Structured interviews tend to employ more closed-response questions in which the valid answers have been pre-planned, rather than open-ended questions. With open-ended questions the respondents provide their answers in their own words, whereas closed-response questions involve a choice of answers provided by the interviewer.

4. The extent of control by the interviewer. In a structured interview, the interviewer explicitly guides or directs the conversation (e.g. ‘Mr. Smith, let’s discuss how your family feels about your problem’) rather than the respondent setting the agenda. In an unstructured interview, the respondent may assume a more active role in the conversation.

Quantitative researchers often favour highly structured, standardized interviews, while qualitative researchers often prefer semi-structured or unstructured approaches. This is consistent with the way data is analysed and interpreted under the two methods (see Ch. 2). It is useful to consider some of the advantages and disadvantages of the different types of interview approaches. These are summarized in Table 12.1.

Table 12.1

Advantages and disadvantages of structured and unstructured interviews

	Advantages	Disadvantages
Structured interviews	May be less time-consuming The same information is collected for all respondents	Responses may not be recorded in the respondents’ own words
Unstructured interviews	Responses may be recorded in the ‘own words’ of the respondents, hence less bias through interpretation The respondent has some input into the research agenda	May be time-consuming Not all the same information is collected for all respondents

The appropriateness of the different interview approaches is determined by the objectives of the researcher. If the researcher simply wishes to collect some basic symptom data, an unstructured interview would be inefficient. However, if the researcher wishes to study people’s conceptualization and interpretation of their illness, an unstructured interview may be quite suitable. Some clinical interviews, such as history taking, are highly structured whereas other clinical interviews, such as those involving management of a long-term problem, may be less so.

Methods of conducting interviews

Since an interview is a conversation, there are several possible ways of conducting it. The interview may be conducted in person (‘face to face’) or by remote means such as by telephone or by using a system such as Skype™. There are a number of advantages associated with face-to-face interviews. (These are also discussed in Chapter 9.) Face-to-face interviews permit the non-verbal reactions of the respondent to be observed and perhaps the development of a closer rapport arising from the more ‘natural’ setting. Interviewers may use their observations of non-verbal cues to supplement the verbal information being provided and use their own non-verbal cues in a similar fashion. This is a particularly important consideration for qualitative researchers. However, the face-to-face interview may require a substantial amount of participant travel time and hence higher costs than for a telephone interview. With certain interview objectives, however, telephone interviews may not be suitable. If the interviewer and his or her credentials are not well known to the interviewee, it is unlikely that participants in a telephone interview would provide valid and reliable information about personal topics. Some people find disclosure of sensitive information to be easier by telephone or by the use of anonymous self-completion questionnaires. The face-to-face interview may be too confrontational or embarrassing for them. Tools such as Skype™ provide an interesting combination of the two methods if the video-cam is enabled.