Compară metode

	Design Ex Post Facto	Cercetare cauzal-comparativă	Cercetarea descriptivă	Cercetare Longitudinală
Domeniu	Design de cercetare	Design de cercetare	Design de cercetare	Design de cercetare
Familie	Process / pipeline	Process / pipeline	Process / pipeline	Process / pipeline
Anul apariției	1960s (systematic codification); concept used in social science from early 20th century	1964	Late 19th century; formalized in social/behavioral sciences ~1960s–1980s	Late 19th–early 20th century; methodologically codified through the 20th century
Autorul original	Formalized by Fred N. Kerlinger; foundational treatment by Donald T. Campbell and Julian C. Stanley	Fred N. Kerlinger	Francis Galton, Karl Pearson (early empirical tradition); formalized in social science by Fred Kerlinger	No single originator; foundational methodological treatments by Stuart Menard and Judith Singer & John Willett
Tip	Non-experimental quantitative research design	Non-experimental quantitative research design	Non-experimental quantitative research design	Quantitative (or mixed) observational research design
Sursa seminală	Kerlinger, F. N. (1964). Foundations of Behavioral Research. Holt, Rinehart and Winston.	Kerlinger, F. N. (1964). Foundations of Behavioral Research. Holt, Rinehart and Winston.	Creswell, J. W. (2014). Research Design: Qualitative, Quantitative, and Mixed Methods Approaches (4th ed.). Sage. ISBN: 978-1452226101	Menard, S. (2002). Longitudinal Research (2nd ed.). Sage Publications. ISBN: 978-0761922841
Denumiri alternative	after-the-fact research, retrospective non-experimental design, causal-comparative design, EPF design	ex post facto research, causal-comparative design, retrospective causal study, CCR	descriptive study, descriptive survey design, observational descriptive research, non-experimental descriptive research	longitudinal study, longitudinal design, prospective longitudinal study, repeated-measures observational study
Înrudite	3	3	3	4
Rezumat	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.	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.	Longitudinal research is an observational design in which the same participants, groups, or units are measured repeatedly over an extended period. Rather than capturing a single snapshot, it tracks change, stability, and temporal sequencing of variables — making it the primary non-experimental strategy for studying development, growth, decline, and the unfolding of causal processes across time.