What is the difference between a structured interview and an unstructured interview, and what are the advantages and disadvantages of each?

Structured interviews are used in psychology when carrying out interviews where the questions are predetermined and in a certain order. The order and structure never changes for any participant.The advantages to structured interviews is that because the questions are put to all participants in the same way, it is more generalisable accross the study. However, it does mean that participants often do not divulge or reveal as much because of the strict design.Unstructured interviews are more about what the participant feels is relevant. There are questions to prompt the participant and to help them stay on topic however participants can talk as much as they like about a certain area of that topic. The advantages to unstructured interviews are that they focus on what is relevant to the participant as they are more open to express their own opinion rather than sticking to answering very limited questions. This can however be disadvantageous as not all participants will be treated in the same way and the data is likely to be more difficult to analyse as it will be more varied.