مقایسهٔ روش‌ها

	مطالعه مورد-شاهدی	مطالعه کوهورت	مطالعه مورد-شاهدی تودرتو
حوزه	اپیدمیولوژی	اپیدمیولوژی	اپیدمیولوژی
خانواده	Process / pipeline	Process / pipeline	Process / pipeline
سال پیدایش	1950s (formal methodology); precursors in the 1920s	Mid-20th century (formal epidemiological design codified ~1950s)	1973–1977
پدیدآور	Janet Lane-Claypon (early precursors, 1926); formalized by Brian MacMahon and Jerome Cornfield in the 1950s–1960s	Doll & Hill (British Doctors Study, 1951); Snow (cholera, 1854)	Nathan Mantel (1973); D. C. Thomas (1977 formalization)
نوع	Observational analytic study design	Observational longitudinal study design	Hybrid observational study design
منبع بنیادین	Schlesselman, J.J. (1982). Case-Control Studies: Design, Conduct, Analysis. Oxford University Press. ISBN: 978-0195027860	Rothman, K. J., Greenland, S., & Lash, T. L. (2008). Modern Epidemiology (3rd ed.). Lippincott Williams & Wilkins. ISBN: 978-0781755641	Thomas, D. C. (1977). Addendum to: Methods of cohort analysis: Appraisal by application to asbestos mining. Journal of the Royal Statistical Society, Series A, 140(4), 469–491.
نام‌های دیگر	case-referent study, case-control design, retrospective case-control, case-control analysis	longitudinal study, follow-up study, panel study, incidence study	NCC study, nested CC design, case-control within cohort, density sampling case-control
مرتبط	6	6	6
خلاصه	A case-control study is a retrospective observational design in which individuals who have developed a disease or outcome of interest (cases) are compared with individuals who have not (controls) to determine whether prior exposure to a putative risk factor differs between the two groups. The primary measure of association is the odds ratio, which approximates the relative risk when the outcome is rare. Case-control studies are especially efficient for investigating rare diseases and generating etiological hypotheses.	A cohort study assembles a group of individuals who share a common starting point — typically freedom from the outcome of interest — and follows them over time to observe who develops the outcome. By comparing incidence rates between exposed and unexposed subgroups, researchers can estimate relative risk and absolute risk differences. Cohort studies are the gold-standard observational design for measuring disease incidence and establishing temporal relationships between exposure and outcome.	A nested case-control study is an efficient observational design embedded within a defined cohort. For each participant who develops the outcome of interest (a case), a small number of matched controls are sampled from those still at risk at the same point in time. This density-sampling strategy yields odds ratios that approximate incidence-rate ratios from the full cohort at a fraction of the data-collection cost — making it the preferred alternative when measuring exposures for all cohort members would be prohibitively expensive or technically demanding.