手法を比較

	縦断的単一事例研究 ― 時間経過に伴う変化の深掘り	複数事例研究
分野	質的手法	質的手法
系統	Process / pipeline	Process / pipeline
提唱年	1984 (Yin's foundational codification); longitudinal case methods in use since early 20th century	1980s–1990s (Yin's first edition 1984; Stake's collective case study concept 1995)
提唱者	Robert K. Yin (systematic codification); roots in clinical and anthropological case tradition	Robert K. Yin (systematic replication logic); Robert E. Stake (naturalistic/collective case tradition)
種類	Qualitative research design	Qualitative research method
原典	Yin, R. K. (2018). Case Study Research and Applications: Design and Methods (6th ed.). Sage. ISBN: 978-1506336169	Yin, R. K. (2018). Case Study Research and Applications: Design and Methods (6th ed.). Sage. ISBN: 978-1506336169
別名	single-case longitudinal design, in-depth longitudinal case study, idiographic longitudinal study, LSCS	comparative case study, multi-site case study, collective case study, cross-case analysis
関連	6	6
概要	A longitudinal single case study is a qualitative research design that follows one bounded unit — a person, organization, program, or community — through multiple points in time. Unlike a cross-sectional snapshot, it captures how phenomena develop, shift, or respond to events across months or years, combining the contextual richness of case study methodology with the temporal depth needed to understand process and change.	Multiple-case study design investigates two or more bounded real-world cases using the same research protocol, then compares findings across cases to identify patterns, contrasts, and explanatory insights that a single case could not produce. Developed primarily through Robert Yin's replication logic and Robert Stake's collective case tradition, the approach is particularly powerful when a researcher needs to determine whether a phenomenon occurs under varied conditions or to test an emerging theoretical explanation against rival contexts.