مقایسهٔ روش‌ها

	رگرسیون کاکس با متغیرهای کمکی وابسته به زمان	مدل فراژتی مشترک برای داده‌های بقای خوشه‌ای
حوزه	تحلیل بقا	تحلیل بقا
خانواده	Survival analysis	Survival analysis
سال پیدایش	1972	1979
پدیدآور	Cox, D. R. (extended formulation by Therneau & Grambsch)	Vaupel, J.W., Manton, K.G. & Stallard, E.
نوع	Semi-parametric hazard regression model	Random effects survival model
منبع بنیادین	Therneau, T. M. & Grambsch, P. M. (2000). Modeling Survival Data: Extending the Cox Model. Springer.	Vaupel, J.W., Manton, K.G. & Stallard, E. (1979). The Impact of Heterogeneity in Individual Frailty on the Dynamics of Mortality. Demography, 16(3), 439–454.
نام‌های دیگر	time-varying covariate Cox model, extended Cox model, Zamana Bağlı Kovaryatlı Cox Regresyonu	shared frailty model, random effects survival model, Frailty Modeli (Paylaşılan Kırılganlık)
مرتبط	4	3
خلاصه	Time-dependent Cox regression is an extension of the standard Cox proportional hazards model, introduced through the counting-process formulation developed by Therneau and Grambsch (2000), that allows one or more predictor variables to take different values at different points in a subject's follow-up period. It is the method of choice whenever a covariate — such as a laboratory measurement, a medication dose, or a disease severity score — changes over time rather than remaining fixed from study entry.	The shared frailty model, introduced by Vaupel, Manton, and Stallard in 1979, extends standard survival regression by incorporating a random effect — the 'frailty' — that captures unobserved heterogeneity among subjects or clusters. When survival outcomes are measured on individuals who share a common environment (patients in the same hospital, members of the same family, animals in the same litter), a frailty term accounts for the within-cluster dependence that ordinary Cox regression ignores.