قارن الطرق

	دراسة حالة وشاهد مستقبلية	دراسة الأتراب
المجال	علم الأوبئة	علم الأوبئة
العائلة	Process / pipeline	Process / pipeline
سنة النشأة	1970s–1990s (formalized alongside nested case-control methods)	Mid-20th century (formal epidemiological design codified ~1950s)
صاحب الطريقة	Evolved from classical retrospective case-control methodology; prospective embedding attributed to modern epidemiological practice (Rothman, Greenland, and others, late 20th century)	Doll & Hill (British Doctors Study, 1951); Snow (cholera, 1854)
النوع	Observational analytic study design	Observational longitudinal study design
المصدر التأسيسي	Rothman, K. J., Greenland, S., & Lash, T. L. (2008). Modern Epidemiology (3rd ed.). Lippincott Williams & Wilkins. ISBN: 978-0781755641	Rothman, K. J., Greenland, S., & Lash, T. L. (2008). Modern Epidemiology (3rd ed.). Lippincott Williams & Wilkins. ISBN: 978-0781755641
الأسماء البديلة	prospective case-control design, ambidirectional case-control, bidirectional case-control, nested case-control (prospective variant)	longitudinal study, follow-up study, panel study, incidence study
ذات صلة	6	6
الملخص	A prospective case-control study embeds the case-control logic within a defined cohort followed forward in time. Cases are identified as they occur, rather than looked up in records after the fact, and controls are sampled from the same prospectively monitored base population. This forward-looking approach allows collection of exposure data before outcome ascertainment, reducing recall bias — the principal weakness of the classic retrospective case-control design — while retaining the efficiency gains of sampling controls rather than enrolling a full cohort.	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.