विधियों की तुलना करें

	पूर्वव्यापी नेस्टेड केस-कंट्रोल अध्ययन	पूर्वव्यापी केस-कंट्रोल अध्ययन
क्षेत्र	महामारी विज्ञान	महामारी विज्ञान
परिवार	Process / pipeline	Process / pipeline
उद्भव वर्ष	1973 (formal description); widely adopted in epidemiology from 1980s onward	1950s–1960s (formal methodology)
प्रवर्तक	Nested case-control formalized by Mantel (1973); retrospective application via historical cohort records	Jerome Cornfield; formalized by Brian MacMahon and others in mid-20th-century epidemiology
प्रकार	Observational analytic study design	Observational analytical study
मौलिक स्रोत	Mantel, N. (1973). Synthetic retrospective studies and related topics. Biometrics, 29(3), 479–486.	Schlesselman, J. J. (1982). Case-Control Studies: Design, Conduct, Analysis. Oxford University Press. ISBN: 978-0195029338
उपनाम	retrospective NCC, nested case-control within retrospective cohort, case-control nested in historical cohort, nested CCR	case-control study, retrospective case-referent study, case-referent design, trohoc study
संबंधित	5	5
सारांश	A retrospective nested case-control study is an efficient observational design in which cases and matched controls are sampled from within an already-assembled retrospective cohort. Exposure data are retrieved from historical records only for selected participants, dramatically reducing data-collection costs while retaining most of the analytic power of the full cohort. It is widely used in pharmacoepidemiology, occupational health, and disease-registry research.	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.