ArticleClinical trials (London, England)2015
Are outcome-adaptive allocation trials ethical?
Article in Clinical trials (London, England), 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 54 papers, 2 of them syntheses that pooled it.
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Who cites it
54 citing papers in PubMed, 2 syntheses or guidelines pooled it.
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- The next phase in Long COVID research: addressing the ethical challenges in trials of disease-modifying treatments.EClinicalMedicine · 2026Review
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- Exploring Bayesian adaptive designs in multi-arm randomized controlled trials with a patient preference arm.Journal of biopharmaceutical statistics · 2025Article
- Adaptive Bayesian Clinical Trials: The Past, Present, and Future of Clinical Research.Journal of clinical medicine · 2025Article
- Implementation of statistical features of a Bayesian two-armed responsive adaptive randomization trial with post hoc analysis of time trend drift.Journal of biopharmaceutical statistics · 2025Article
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- Seamless trials in oncology: A cross-sectional analysis of characteristics and reporting.PloS one · 2024Article
- Bayesian Strategies in Rare Diseases.Therapeutic innovation & regulatory science · 2023Review
- The value of a two-armed Bayesian response adaptive randomization trial.Journal of biopharmaceutical statistics · 2023Article
- Non-static framework for understanding adaptive designs: an ethical justification in paediatric trials.Journal of medical ethics · 2022Article
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- COVID-19 and the generation of novel scientific knowledge: Research questions and study designs.Journal of evaluation in clinical practice · 2021Article
- Evaluating Bayesian adaptive randomization procedures with adaptive clip methods for multi-arm trials.Statistical methods in medical research · 2021Article
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Abstract
Randomization is firmly established as a cornerstone of clinical trial methodology. Yet, the ethics of randomization continues to generate controversy. The default, and most efficient, allocation scheme randomizes patients equally (1:1) across all arms of study. However, many randomized trials are using outcome-adaptive allocation schemes, which dynamically adjust the allocation ratio in favor of the better performing treatment arm. Advocates of outcome-adaptive allocation contend that it better accommodates clinical equipoise and promotes informed consent, since such trials limit patient-subject exposure to sub-optimal care. In this essay, we argue that this purported ethical advantage of outcome-adaptive allocation does not stand up to careful scrutiny in the setting of two-armed studies and/or early-phase research.
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