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Title The continuing unethical conduct of underpowered clinical trials
Author Halpern SD, Karlawish JHT, Berlin JA
Year 2002
Journal Halpern SD, Karlawish JHT, Berlin JA: The continuing unethi JAMA-Journal of the American Medical Association
Volume 288
Issue

Pages 358-362.
Publisher

Link_for_PDF_for_Education

Link for Open Access

DOI

Link for DOI

Web_Access_Paper http://jama.jamanetwork.com/article.aspx?articleid=195126#qundefined [proprietary]
Contributed_by Peter Bacchetti
Commentary This paper largely restated supposed dogma, without providing supporting evidence or reasoning. It sought to refute two arguments for why studies with lower than conventional power are not necessarily unethical. The arguments in question both rely on the idea that a study need not be conclusive to have sufficient value: one is that later meta-analyses can make use of inconclusive or imprecise information to build more conclusive and precise evidence; the other is that a study's estimates and confidence intervals provide some information, and some is better than none. The authors' counterarguments relied on presuming the issue in question: that only conclusive evidence has enough value to make a study ethical. For example, they simply asserted that the value of an estimate and confidence interval that do not provide conclusive evidence "generally is insufficient to justify exposing individuals to the common risks and burdens of research." No support for this presumption was given. It led to their main conclusion, that "underpowered" studies are ethical only if they are part of a program of research designed to lead to conclusive evidence: either a phase 1 or 2 clinical trial or part of a prospective meta-analysis. Other key presumptions or assertions with no supporting reasoning included: that "adequate" power is 80% or greater; a complicated proposal for the effect size that must be used for calculating power; that studies will always be interpreted simply as either "positive" or "negative"; that having less than 80% power "shifts the risk-benefit calculus" in an unfavorable direction; that participants would rather be a small part of a large trial than a relatively larger part of a smaller one. All of these have been disputed or shown to be incorrect. Some evidence and reasoning was given concerning the (lack of) potential value from contributing to meta-analyses. This gave considerable emphasis to the risk of studiesí results not being made accessible, but did not explain why having a small sample size should be considered unethical rather than focusing on failure to disseminate results as being what is unethical. Further discussion of the issues is available here.
Additional_Information

Reference_Subject Biostat_Ethics
Disclaimer The views expressed within CTSpedia are those of the author and must not be taken to represent policy or guidance on the behalf of any organization or institution with which the author is affiliated.
Topic revision: r2 - 26 Mar 2013 - 00:55:32 - PeterBacchetti
 

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