Are outcome-adaptive allocation trials ethical?. (April 2015)

• Record Type: Journal Article
• Authors: Hey, Spencer Phillips; Kimmelman, Jonathan
• Is Part Of: Clinical trials. Volume 12:Number 2(2015)
• Page Start: 102
• Page End: 106
• Publication Date: 2015-04
• Subjects: Adaptive randomization -- ethics -- equipoise -- therapeutic misconception; 615.5072405
• DOI: 10.1177/1740774514563583
• Languages: English
• ISSNs: 1740-7745

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.