What are structured and unstructured interview methods?

Structured and unstructured interview methods represent distinct approaches to data collection. Structured interviews employ a predetermined, identical set of questions administered systematically to all participants, facilitating quantitative or qualitative statistical analysis. Unstructured interviews, conversely, utilize a flexible, conversational format guided by broad topics, aiming for in-depth qualitative understanding. The key principle of structured interviews lies in standardization to maximize reliability and reduce interviewer bias, requiring rigorous instrument development and strict adherence to the script. Unstructured interviews prioritize flexibility and depth, relying significantly on the interviewer's skill to probe and adapt organically. Structured methods excel in testing specific hypotheses across larger groups, whereas unstructured methods are essential for exploratory research investigating complex phenomena, meanings, and lived experiences. Careful design of the interview guide and extensive piloting are crucial prerequisites for structured interviews; achieving depth while managing breadth and documenting context effectively are primary considerations for unstructured interviews. Structured interviews are widely applied in large-scale surveys and standardized assessments where generalizability and comparability are paramount. Unstructured interviews are fundamental in ethnographic work, case study research, and developing grounded theory, offering unique insights into participant perspectives and contexts that structured formats may miss.