手法を比較

	クロスオーバー適応実験	適応的無作為化比較試験
分野	実験計画法	実験計画法
系統	Process / pipeline	Process / pipeline
提唱年	Late 1990s–2000s	1980s–2000s (formalized; earlier sequential testing roots from Wald, 1947)
提唱者	Developed through convergence of crossover trial methodology (Senn, Williams) and adaptive design methods (Bauer, Köhne, Chow, Chang)	Donald Berry and others; foundational adaptive trial methods developed through 1980s–2000s biostatistics literature
種類	Experimental design — hybrid adaptive/crossover	Experimental design — adaptive variant of RCT
原典	Chow, S.-C., & Chang, M. (2008). Adaptive Design Methods in Clinical Trials. Chapman & Hall/CRC. ISBN: 978-1584888468	Chow, S.-C., & Chang, M. (2008). Adaptive Design Methods in Clinical Trials. Chapman & Hall/CRC. ISBN: 978-1584887690
別名	adaptive crossover trial, adaptive crossover design, crossover adaptive trial, ACE design	Adaptive RCT, Response-adaptive RCT, Adaptive clinical trial, Platform trial
関連	5	6
概要	An adaptive crossover experiment combines the within-subject efficiency of crossover designs — where each participant receives multiple treatments in sequence — with pre-specified adaptive rules that allow trial parameters to be modified based on interim data. Each participant acts as their own control across treatment periods, while ongoing accumulating evidence can trigger pre-planned changes such as sample size re-estimation, treatment arm dropping, or allocation ratio adjustment, all governed by a formal adaptation plan to preserve inferential validity.	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.