The type of interview chosen will depend on the purpose of the interview. Phenomenological interviews are used to explore the lived experience (Hasty & Shattell 2005) while narrative interviewing is conversational in style. Narrative interviewing allows participants to bring in anything they consider relevant and allows them to articulate their knowledge and experience though storied accounts (Bates 2004).

The more structured an interview is, the greater the standardisation of the questions and the questioning. Structured interviews are sometimes called quantitative interviews and generally involve the administration of structured interview schedules, such as a questionnaire. Interviewers using structured questionnaires are required to ask a predetermined sequence of questions in a consistent manner. Most often the questions are close-ended and require a fixed-choice response (Britten 1995), meaning that the range of possible responses is predetermined. Semi-structured interviews involve the use of topics or broad questions (Polit & Beck 2006), and are not as controlled or fixed as the structured interview. Interviewers normally have a list of trigger or guide questions; there is space for dialogue and for the participant to offer responses that are not predetermined.

Unstructured interviews are also referred to as in-depth or qualitative interviews. The questions are open-ended and there are no predetermined responses presented to participants. As with the semi-structured interview, researchers employing unstructured interviews also have a guide to cover the major areas which will be explored (Wimpenny & Gass 2000). Unlike the structured interview, the unstructured interview is characterised by a participant guided approach. The nature and order of questioning will vary between participants and will be dependent on the issues that they raise in relation to the phenomenon being studied.

Interviews can occur between a researcher and individual participants, or between a researcher and two or more participants simultaneously. Group interviews are more commonly referred to as ‘focus groups’ and were first used in market research (Sofaer 2002). Focus groups usually comprise people who may be unknown to one another but who share a common characteristic that is of interest to the researcher. An increasing number of studies demonstrate the utility of the focus group in conducting health-related research in culturally and linguistically diverse populations. Other types of group interviewing can include friend or partner dyads (Highet 2003), or family interviewing in which members of a family group are interviewed together (Astedt-Kurki et al 2001).

Many interviews are conducted face-to-face but with advances in technology they can also be conducted by telephone, videolink or online. Use of email, private chat rooms and instant messaging is becoming increasingly common and these methods have definite advantages, especially in relation to cost. Interviews conducted using these technologies can generate cost savings associated with transcriptions, travel and time. They can also open participation up to people from distant locations who would otherwise be unable to participate in interviews because of distance. Davis et al (2004) described using online methods to interview men on their experiences of using the internet to find sexual partners and how safe sex is negotiated in these situations. Use of this technology meant that men who might not otherwise have been willing to present for a face-to-face interview, due to the sensitive nature of the subject matter, were willing to participate.

Despite the perceived advantages of lower costs, greater convenience and perception of greater anonymity, the use of telephone and online technologies can make it more difficult to establish rapport and trust and may ultimately influence the quality of the data obtained (Pridemore et al 2005). Furthermore, Davis et al (2004) noted difficulties with the flow, amount and quality of conversation obtained online, pointing out that a 120-minute online interview generated seven pages of text while a 90-minute face-to-face interview resulted in 30–40 pages.

As in any research process, obtaining informed consent is an essential element of the research interview. When nurses and other health workers conduct research interviews with patients/clients, there is room for confusion with the clinical role (Britten 1995). For this reason, Britten (1995) advised against researchers interviewing their own patients/clients, but should this occur, it is very important that informed consent is obtained. As a part of this process, potential participants need to be informed that they do not have to participate, and that they have the right to withdraw at any time, and that they can stop the interview with no negative consequences to them or their relationship with their health care provider.

Participants have the right to privacy and security of data. Interviewers need to ensure that the site and product of the interview remains private and confidential, and that any reports or papers arising from the study are presented in such a way as to maintain participant confidentiality. To ensure maintenance of privacy and confidentiality, and to ensure that the data are not misused, most institutional ethics committees have strict rules about secure storage and effective destruction of interview data.

The issue of power is one that features largely in the discourses around research interviews. While research participants maintain significant power in that they get to decide what and how much they will disclose, Donalek (2005) pointed out that there is power in being positioned as an expert, and that power has the potential to be abused. The power dynamic is further complicated if there is a pre-existing power relationship between the interviewer and participant, such as may occur when academics are interviewing students, or hospital staff are interviewing patients for research purposes. In situations such as these, people may feel compelled to participate in research interviews and may aim to please the interviewer by providing the responses they think are desired.

Because of the way that nurses use interviewing in their normal daily practice, it can be assumed that they will be able to engage easily in research interviews. Indeed, as Donalek (2005, p. 124) noted, it appears ‘deceptively simple’. However, in describing their experiences of collecting interview data, Tollefson et al (2001, p. 259) stated: ‘interviewing for the purpose of gathering qualitative information for research purposes is different from interviewing for any other purpose’. They go on to highlight the importance of interview preparation, and recognition of factors such as power relationships that will impact on the nature and quality of data that can be collected (Tollefson et al 2001).