Compara mètodes

	Investigació-acció	Investigació per estudi de cas	Investigació amb grups focals
Camp	Recerca qualitativa	Qualitativa	Qualitativa
Família	Process / pipeline	Process / pipeline	Process / pipeline
Any d'origen	1946	1984 (seminal codification)	1940s (sociological origin); modern applied form from the 1980s–1990s
Autor original	Kurt Lewin; expanded by Kemmis, McTaggart, Reason & Bradbury	Robert K. Yin (systematised in Case Study Research, 1984)	Robert K. Merton (sociological precursor, 1940s); popularised in applied research by Richard A. Krueger
Tipus	Method	Qualitative research design	Qualitative data collection method
Font seminal	Lewin, K. (1946). Action research and minority problems. Journal of Social Issues, 2(4), 34–46.	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
Àlies	Participatory Action Research, PAR, Collaborative Inquiry	Vaka Çalışması (Case Study), case study design, case study methodology	focus group discussion, FGD, group interview, Odak Grup Araştırması
Relacionats	1	5	6
Resum	Action research is a collaborative research methodology in which researchers work with practitioners and community members to investigate a problem, implement change, and evaluate outcomes, cycling through reflection, action, and learning. Developed by Kurt Lewin (1946), action research bridges research and practice, aiming simultaneously to produce knowledge and practical improvement.	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.