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Semin Reprod Med 2003; 21(1): 055-064
DOI: 10.1055/s-2003-39995
Copyright © 2003 by Thieme Medical Publishers, Inc., 333 Seventh Avenue, New York, NY 10001, USA. Tel.: +1(212) 584-4662

Randomized Clinical Trials: The Meeting Place of Medical Practice and Clinical Research

Edward G. Hughes
  • Department of Obstetrics and Gynecology, McMaster University, Hamilton, Ontario, Canada
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Publication History

Publication Date:
12 June 2003 (online)

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ABSTRACT

Randomized clinical trials (RCTs) have been used to assess interventions affecting health since biblical times. They provide the most valid means of measuring the true effects of intervention compared with no treatment or placebo. Although they can also be used to assess the value of diagnostic tests, this article focuses on randomized trials in the context of treatment. Key elements of an RCT include: the explicit definition of a clinically relevant question; the identification of an appropriate sample of patients; a clearly defined and reproducible intervention; an appropriate intervention and comparator; clinically relevant, measurable outcomes; and appropriate tools for measurement and analysis. It is also essential to establish that the question posed is ethical, the methods of study are valid, and that follow-up is complete, with an “intent to treat” analysis. Results are best presented using both proportions and absolute numbers. By providing clinical decision-makers with numbers needed to treat or harm, decisions may be better informed and easier to understand, than if proportions alone are used.

KEYWORDS

Randomized controlled trial - random allocation - clinical epidemiology - treatment effectiveness

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