手法を比較

	事後調査デザイン	因果比較研究
分野	研究デザイン	研究デザイン
系統	Process / pipeline	Process / pipeline
提唱年	1960s (systematic codification); concept used in social science from early 20th century	1964
提唱者	Formalized by Fred N. Kerlinger; foundational treatment by Donald T. Campbell and Julian C. Stanley	Fred N. Kerlinger
種類	Non-experimental quantitative research design	Non-experimental quantitative research design
原典	Kerlinger, F. N. (1964). Foundations of Behavioral Research. Holt, Rinehart and Winston.	Kerlinger, F. N. (1964). Foundations of Behavioral Research. Holt, Rinehart and Winston.
別名	after-the-fact research, retrospective non-experimental design, causal-comparative design, EPF design	ex post facto research, causal-comparative design, retrospective causal study, CCR
関連	3	3
概要	Ex post facto design is a non-experimental quantitative research approach in which the researcher investigates a phenomenon after it has already occurred, examining pre-existing differences between groups to explore potential causal or associative relationships. Because the independent variable cannot be manipulated — it happened in the past — the design relies on careful group selection, retrospective data collection, and statistical controls to approximate causal inference without experimental intervention.	Causal-comparative research is a non-experimental quantitative design in which the researcher compares two or more groups that already differ on an independent variable — one that was not manipulated — to investigate possible causes or consequences of that difference. Because group membership is pre-existing rather than randomly assigned, the design can suggest causal relationships but cannot establish them with the certainty of a true experiment. It is widely used in education, psychology, and social sciences when experimental manipulation is impractical or unethical.