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Letters |

Informing Patients of Uncertainty in Clinical Trials

Scott D. Halpern, BS; Jason H. T. Karlawish, MD; Charles Weijer, MD, PhD
JAMA. 2001;285(21):2713-2714. doi:10.1001/jama.285.21.2713-a.
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To the Editor: Drs Djulbegovic and Clarke mistakenly suggest that the "fundamental ethical challenge" of equivalence trials is that they entail an a priori assumption that one intervention is superior to another.1

The authors claim that "[t]he design of a clinical trial should be a function of the uncertainty principle," while simultaneously acknowledging that "prior research should not have proved a difference between the alternate therapies in outcomes to be assessed." But according to the uncertainty principle, only the individual physician's views, and not prior knowledge, should be considered.2 Among the problems with this principle are that it does not explain what counts as medical knowledge, where medical knowledge comes from, or what is the purpose of a randomized controlled trial (RCT).3 It is therefore inadequate to answer questions about scientific design.


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