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	تجربة عشوائية متصالبة محكومة	التجربة العشوائية التكيفية - التجربة العشوائية التكيفية
المجال	التصميم التجريبي	التصميم التجريبي
العائلة	Process / pipeline	Process / pipeline
سنة النشأة	1960s (Grizzle 1965 for statistical foundations); widely used in clinical research since the 1970s	1980s–2000s (formalized; earlier sequential testing roots from Wald, 1947)
صاحب الطريقة	Early formalized by statisticians including Bradford Hill and colleagues in clinical trials; theoretical framework developed by Grizzle (1965) and later Senn (2002)	Donald Berry and others; foundational adaptive trial methods developed through 1980s–2000s biostatistics literature
النوع	Experimental within-subject design	Experimental design — adaptive variant of RCT
المصدر التأسيسي	Senn, S. (2002). Cross-over Trials in Clinical Research (2nd ed.). Wiley. ISBN: 978-0471496533	Chow, S.-C., & Chang, M. (2008). Adaptive Design Methods in Clinical Trials. Chapman & Hall/CRC. ISBN: 978-1584887690
الأسماء البديلة	crossover RCT, crossover trial, within-subject RCT, AB/BA crossover design	Adaptive RCT, Response-adaptive RCT, Adaptive clinical trial, Platform trial
ذات صلة	5	6
الملخص	A crossover randomized controlled trial (crossover RCT) is an experimental design in which each participant receives all study interventions in a randomized sequence, separated by a washout period. Because every participant serves as their own control, within-subject variability is eliminated from the treatment comparison, yielding greater statistical power per participant than a parallel-group RCT of equal size.	An adaptive randomized controlled trial (adaptive RCT) is an experimental design in which pre-specified rules allow modifications to the trial while it is ongoing — such as changing allocation ratios, dropping underperforming arms, or stopping early for efficacy or futility — based on accumulating interim data. These adaptations are planned before the trial starts and governed by statistical rules to preserve Type I error control and validity.