方法对比

	交叉 A/B 测试	交叉随机对照试验
领域	实验设计	实验设计
方法族	Process / pipeline	Process / pipeline
起源年份	1949 (crossover design); 2000s (online A/B application)	1960s (Grizzle 1965 for statistical foundations); widely used in clinical research since the 1970s
提出者	Crossover design: E. J. Williams (1949); A/B testing framework: Ronald Fisher (experimental roots); modern online application widely attributed to Google and Microsoft experimentation teams	Early formalized by statisticians including Bradford Hill and colleagues in clinical trials; theoretical framework developed by Grizzle (1965) and later Senn (2002)
类型	Within-subject controlled experiment	Experimental within-subject design
开创性文献	Jones, B., & Kenward, M. G. (2014). Design and Analysis of Cross-Over Trials (3rd ed.). Chapman and Hall/CRC. ISBN: 9781439861424	Senn, S. (2002). Cross-over Trials in Clinical Research (2nd ed.). Wiley. ISBN: 978-0471496533
别名	within-subject A/B test, crossover split test, repeated-measures A/B test, AB crossover experiment	crossover RCT, crossover trial, within-subject RCT, AB/BA crossover design
相关	6	5
摘要	A crossover A/B test is an experimental design in which the same participants or units are exposed to both treatment A and treatment B in sequence, with each serving as their own control. By eliminating between-subject variability, the design achieves higher statistical power than a standard parallel A/B test at the same sample size, but it requires careful handling of carryover effects and time-period confounds.	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.