قارن الطرق

	نموذج كوكس للمخاطر النسبية	دراسة الأتراب
المجال	علم الأوبئة	علم الأوبئة
العائلة	Process / pipeline	Process / pipeline
سنة النشأة	1972	Mid-20th century (formal epidemiological design codified ~1950s)
صاحب الطريقة	Sir David Roxbee Cox	Doll & Hill (British Doctors Study, 1951); Snow (cholera, 1854)
النوع	Semi-parametric regression model	Observational longitudinal study design
المصدر التأسيسي	Cox, D. R. (1972). Regression models and life-tables. Journal of the Royal Statistical Society: Series B (Methodological), 34(2), 187–202.	Rothman, K. J., Greenland, S., & Lash, T. L. (2008). Modern Epidemiology (3rd ed.). Lippincott Williams & Wilkins. ISBN: 978-0781755641
الأسماء البديلة	Cox regression, Cox PH model, proportional hazards model, CPH	longitudinal study, follow-up study, panel study, incidence study
ذات صلة	5	6
الملخص	The Cox proportional hazards model is a semi-parametric regression method that estimates the effect of one or more covariates on the hazard — the instantaneous rate of an event such as death, relapse, or failure — while making no assumption about the shape of the baseline hazard function. Introduced by David Cox in 1972, it is the dominant tool for multivariable survival analysis in clinical and epidemiological research.	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.