手法を比較

	ベイズ的無作為化臨床試験	フェーズII臨床試験 ― 初期有効性と用量評価
分野	疫学	疫学
系統	Process / pipeline	Process / pipeline
提唱年	1980s–2000s (formal methodology consolidated ~2004–2006)	1960s–1970s (formalised in US federal drug regulation)
提唱者	Donald A. Berry and David J. Spiegelhalter (applied Bayesian inference formally to RCT design)	U.S. Food and Drug Administration / ICH E8 guidelines (institutionalised framework)
種類	Randomized experimental study with Bayesian inference	Interventional clinical study design
原典	Spiegelhalter, D. J., Abrams, K. R., & Myles, J. P. (2004). Bayesian Approaches to Clinical Trials and Health-Care Evaluation. Wiley. ISBN: 978-0471499756	Friedman, L. M., Furberg, C. D., DeMets, D. L., Reboussin, D. M., & Granger, C. B. (2015). Fundamentals of Clinical Trials (5th ed.). Springer. ISBN: 978-3319185392
別名	Bayesian RCT, Bayesian adaptive trial, Bayesian clinical trial design, BRCT	Phase 2 trial, Phase II study, early efficacy trial, proof-of-concept trial
関連	5	6
概要	A Bayesian randomized clinical trial (Bayesian RCT) combines the rigour of random treatment allocation with Bayesian statistical inference, allowing researchers to incorporate prior evidence and update beliefs continuously as trial data accumulate. Unlike the classical frequentist RCT, it yields direct probability statements about treatment effects and supports pre-specified adaptive stopping rules based on posterior probabilities.	A Phase II clinical trial is the second stage in the drug or intervention development pipeline, conducted after Phase I safety testing. Its primary goal is to assess whether the intervention shows preliminary efficacy signals in a relevant patient population at the dose established in Phase I, while continuing to characterise the safety and tolerability profile. Phase II trials are generally smaller than Phase III confirmatory trials and serve as critical go/no-go decision points before large-scale investment.