방법 비교

	기술 연구	Ex Post Facto Design
분야	연구설계	연구설계
계열	Process / pipeline	Process / pipeline
기원 연도	Late 19th century; formalized in social/behavioral sciences ~1960s–1980s	1960s (systematic codification); concept used in social science from early 20th century
창시자	Francis Galton, Karl Pearson (early empirical tradition); formalized in social science by Fred Kerlinger	Formalized by Fred N. Kerlinger; foundational treatment by Donald T. Campbell and Julian C. Stanley
유형	Non-experimental quantitative research design	Non-experimental quantitative research design
원전	Creswell, J. W. (2014). Research Design: Qualitative, Quantitative, and Mixed Methods Approaches (4th ed.). Sage. ISBN: 978-1452226101	Kerlinger, F. N. (1964). Foundations of Behavioral Research. Holt, Rinehart and Winston.
별칭	descriptive study, descriptive survey design, observational descriptive research, non-experimental descriptive research	after-the-fact research, retrospective non-experimental design, causal-comparative design, EPF design
관련	3	3
요약	Descriptive research is a non-experimental quantitative design that systematically documents the characteristics, frequencies, or distributions of variables in a defined population at a given point in time. It answers 'what is' questions — who, what, when, where, and how much — without manipulating variables or drawing causal conclusions. It is one of the most widely used research designs across the social, behavioral, health, and education sciences.	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.