Determining the sample size in a clinical trial

Adrienne Kirby, Val Gebski and Anthony C Keech
Med J Aust 2002; 177 (5): . || doi: 10.5694/j.1326-5377.2002.tb04759.x
Published online: 2 September 2002

Sample size must be planned carefully to ensure that the research time, patient effort and support costs invested in any clinical trial are not wasted. Item 7 of the CONSORT statement relates to the sample size and stopping rules of studies (see Box 1); it states that the choice of sample size needs to be justified.1

  • NHMRC Clinical Trials Centre, University of Sydney, Camperdown, NSW.



The authors thank Rhana Pike, publications officer, for her assistance in preparing this article.

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  • 6. Gebski V, Marschner I, Keech AC. Specifying objectives and outcomes for clinical trials. Med J Aust 2002; 176: 491-492. <eMJA full text>


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