قارن الطرق

	تجربة عشوائية عنقودية متعددة الأذرع	Cluster Randomized Controlled Trial
المجال	التصميم التجريبي	التصميم التجريبي
العائلة	Process / pipeline	Process / pipeline
سنة النشأة	1990s–2000s (systematic formalization)	1978–1980s
صاحب الطريقة	Building on cluster randomization (Donner & Klar) and multi-arm trial methods developed in clinical and public health research	Cornfield (1978); systematised by Donner and colleagues (1980s)
النوع	Experimental design	Experimental design
المصدر التأسيسي	Donner, A., & Klar, N. (2000). Design and Analysis of Cluster Randomization Trials in Health Research. Arnold. ISBN: 978-0340691533	Donner, A., & Klar, N. (2000). Design and Analysis of Cluster Randomization Trials in Health Research. Arnold. ISBN: 978-0340652978
الأسماء البديلة	multi-arm cluster RCT, cluster-randomized multi-group trial, multi-arm group-randomized trial, CRCT multi-arm	cluster RCT, group-randomized trial, community randomized trial, cluster-randomized experiment
ذات صلة	6	4
الملخص	A cluster randomized multi-arm experiment assigns intact groups — such as schools, clinics, or villages — rather than individuals to three or more experimental conditions simultaneously. Randomization occurs at the cluster level to prevent contamination between arms, while the multi-arm structure allows simultaneous evaluation of several interventions against a common control or each other, improving efficiency over a series of two-arm studies.	A cluster randomized controlled trial (cluster RCT) is an experimental design in which intact social or organisational groups — such as schools, clinics, villages, or workplaces — are randomly assigned to treatment conditions rather than individual participants. Outcomes are still measured at the individual level, but the unit of randomization is the cluster. This design is essential when an intervention is delivered to whole groups, when there is a risk of contamination between participants in the same setting, or when individual randomization is logistically or ethically impractical.