Determining the sample size in a clinical trial

Kirby, Adrienne; Gebski, Val; Keech, Anthony C

doi:10.5694/j.1326-5377.2002.tb04759.x

Topics

Statistics, epidemiology and research design

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.

Correspondence: enquiry@ctc.usyd.edu.au

Acknowledgements:

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

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