手法を比較

	実用的症例対照研究	後向き症例対照研究
分野	疫学	疫学
系統	Process / pipeline	Process / pipeline
提唱年	1950s–1960s (classical); pragmatic framing 1967–2000s	1950s–1960s (formal methodology)
提唱者	Evolved from classical case-control methodology (Dorn, 1954; Cornfield, 1956); pragmatic framing formalized by Schwartz & Lellouch (1967)	Jerome Cornfield; formalized by Brian MacMahon and others in mid-20th-century epidemiology
種類	Observational epidemiological study design	Observational analytical study
原典	Rothman, K. J., Greenland, S., & Lash, T. L. (2008). Modern Epidemiology (3rd ed.). Lippincott Williams & Wilkins. ISBN: 978-0781755641	Schlesselman, J. J. (1982). Case-Control Studies: Design, Conduct, Analysis. Oxford University Press. ISBN: 978-0195029338
別名	real-world case-control study, pragmatic case-control design, effectiveness case-control study, PCCS	case-control study, retrospective case-referent study, case-referent design, trohoc study
関連	6	5
概要	A pragmatic case-control study is an observational design that compares individuals who have developed a disease or outcome (cases) with those who have not (controls), using data collected under routine real-world conditions rather than strictly controlled experimental settings. Exposure histories are reconstructed from clinical records, registries, or administrative databases. The design is chosen when a conventional explanatory case-control study would be impractical, unethical, or too narrow to inform actual clinical or public-health decisions.	A retrospective case-control study identifies individuals who already have an outcome of interest (cases) and a comparable group without it (controls), then looks backward in time using existing records to determine prior exposure to a suspected risk factor. The primary measure of association is the odds ratio. This design is especially efficient for studying rare diseases or outcomes with long latency periods, since the outcome has already occurred before the study begins.