When designing an interview schedule, it is imperative to ask questions that are likely to yield as much information about the study phenomenon as possible and also be able to address the aims and objectives of the research. In a qualitative interview, good questions should be open-ended (ie, require more than a yes/no answer), neutral, sensitive and understandable. It is usually best to start with questions that participants can answer easily and then proceed to more difficult or sensitive topics. This can help put respondents at ease, build up confidence and rapport and often generates rich data that subsequently develops the interview further.
As in any research, it is often wise to first pilot the interview schedule on several respondents prior to data collection proper. This allows the research team to establish if the schedule is clear, understandable and capable of answering the research questions, and if, therefore, any changes to the interview schedule are required. The length of interviews varies depending on the topic, researcher and participant. However, on average, healthcare interviews last 20-60 minutes. Interviews can be performed on a one-off or, if change over time is of interest, repeated basis, for example exploring the psychosocial impact of oral trauma on participants and their subsequent experiences of cosmetic dental surgery.