So sánh phương pháp

	Phỏng vấn sâu theo chiều dọc	Phỏng vấn bán cấu trúc
Lĩnh vực	Phương pháp luận khảo sát	Định tính
Họ	Process / pipeline	Process / pipeline
Năm ra đời	1990s–2000s (as a formalised qualitative method)	1946 (Merton & Kendall); codified as a standard method through the 1980s–1990s
Người khởi xướng	Rooted in qualitative longitudinal research traditions; systematised by Johnny Saldana	Robert K. Merton and Patricia Kendall (focused interview, 1946); further systematised by Steinar Kvale
Loại	Qualitative longitudinal data collection technique	Qualitative research method
Công trình gốc	Saldana, J. (2003). Longitudinal Qualitative Research: Analyzing Change Through Time. AltaMira Press. ISBN: 978-0759103917	Kvale, S., & Brinkmann, S. (2009). InterViews: Learning the Craft of Qualitative Research Interviewing (2nd ed.). Sage. ISBN: 978-0761925422
Tên gọi khác	repeated in-depth interview, longitudinal qualitative interview, panel qualitative interview, longitudinal IDI	guided interview, semi-standardized interview, focused interview, SSI
Liên quan	5	6
Tóm tắt	Longitudinal in-depth interviewing is a qualitative data collection technique in which the same participants are interviewed in depth on multiple occasions across a defined time span. By revisiting the same people over weeks, months, or years, researchers can trace how experiences, identities, attitudes, and meanings change — something a single interview cannot reveal. It is widely used in life-course research, health studies, education, and social policy.	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.