قارن الطرق

	تقييم الأثر السببي متعدد الفترات	نموذج الهياكل الهامشية (MSM)
المجال	الاستدلال السببي	الاستدلال السببي
العائلة	Regression model	Regression model
سنة النشأة	2000s–2010s	2000
صاحب الطريقة	Developed through EU policy evaluation practice (European Commission); formalized by Lechner, Caliendo, and related econometricians	James M. Robins, Miguel A. Hernan, Babette Brumback
النوع	Causal inference / quasi-experimental evaluation	Causal model / semiparametric weighting
المصدر التأسيسي	Caliendo, M., & Kopeinig, S. (2008). Some Practical Guidance for the Implementation of Propensity Score Matching. Journal of Economic Surveys, 22(1), 31-72.	Robins, J. M., Hernan, M. A., & Brumback, B. (2000). Marginal structural models and causal inference in epidemiology. Epidemiology, 11(5), 550-560.
الأسماء البديلة	multi-period CIE, longitudinal counterfactual evaluation, dynamic counterfactual impact evaluation, multi-wave CIE	MSM, MSM-IPTW, marginal structural Cox model, weighted structural model
ذات صلة	4	5
الملخص	Multi-period Counterfactual Impact Evaluation (CIE) estimates the causal effect of a policy or program by constructing what would have happened to treated units across multiple time periods had they not been treated. Unlike single-period evaluations, it tracks treatment effects as they evolve over time, capturing dynamic, delayed, or fading impacts that a two-period comparison would miss.	A marginal structural model is a causal modeling framework designed to estimate the effect of a time-varying treatment in the presence of time-varying confounders that are themselves affected by prior treatment. By reweighting observations with inverse probability of treatment weights, MSMs create a pseudo-population in which confounding is eliminated, enabling unbiased estimation of causal treatment contrasts even when standard regression adjustments would fail.