手法を比較

	半構造化インタビュー	ケーススタディリサーチ（Case Study Research）	フォーカスグループリサーチ
分野	質的手法	質的手法	質的手法
系統	Process / pipeline	Process / pipeline	Process / pipeline
提唱年	1946 (Merton & Kendall); codified as a standard method through the 1980s–1990s	1984 (seminal codification)	1940s (sociological origin); modern applied form from the 1980s–1990s
提唱者	Robert K. Merton and Patricia Kendall (focused interview, 1946); further systematised by Steinar Kvale	Robert K. Yin (systematised in Case Study Research, 1984)	Robert K. Merton (sociological precursor, 1940s); popularised in applied research by Richard A. Krueger
種類	Qualitative research method	Qualitative research design	Qualitative data collection method
原典	Kvale, S., & Brinkmann, S. (2009). InterViews: Learning the Craft of Qualitative Research Interviewing (2nd ed.). Sage. ISBN: 978-0761925422	Yin, R.K. (2018). Case Study Research and Applications: Design and Methods (6th ed.). Sage. ISBN: 978-1506336169	Krueger, R.A. & Casey, M.A. (2014). Focus Groups: A Practical Guide for Applied Research (5th ed.). Sage. ISBN: 978-1483365244
別名	guided interview, semi-standardized interview, focused interview, SSI	Vaka Çalışması (Case Study), case study design, case study methodology	focus group discussion, FGD, group interview, Odak Grup Araştırması
関連	6	5	6
概要	The semi-structured interview is a qualitative data-collection method in which the researcher prepares a set of key questions or topic areas in advance but remains free to probe, follow up, and reorder as the conversation evolves. Unlike structured interviews — which fix every question and sequence — or unstructured interviews — which are entirely open — the semi-structured format balances comparability across participants with the flexibility needed to capture the depth and nuance of individual perspectives. It is the most widely used interview format in social science, health, and education research.	Case study research is a qualitative research design that investigates a specific phenomenon, individual, group, organisation, or event in depth within its real-world context. Systematised by Robert K. Yin in 1984, it supports single-case and multiple-case designs and draws on multiple data sources — interviews, observation, documents, and artefacts — to build a rich, contextualised account of a bounded unit.	Focus group research is a qualitative data-collection method in which a trained moderator guides structured discussions with homogeneous groups of six to ten participants to explore ideas, attitudes, and perceptions on a defined topic. Developed from sociological roots in the 1940s and systematised for applied research by Krueger and Casey, the method leverages group interaction as a data source — revealing not just what people think, but how they negotiate and articulate views in a social setting.