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The Value of Small Clinical Trials

  • K. D. MacRae
Part of the Recent Results in Cancer Research book series (RECENTCANCER, volume 111)

Abstract

Large clinical trials and overviews which pool several clinical trials addressing substantially the same question have an important role in clinical research, viz., the detection of small or moderate differences between treatments where the outcome is an important one, such as survival. Also, large numbers give narrow confidence intervals for the estimate of the treatment effect. However, small clinical trials still have an important part to play. Firstly, pilot studies need to be carried out before a large trial is begun. Secondly, in the treatment of certain diseases, especially where treatment is aimed at relief of symptoms, it may be felt that only large differences between treatments are of interest. Thirdly, it may be difficult to carry out a large clinical trial because of ethical or other problems, but a small trial may be able to provide useful pragmatic information. The important statistical concepts are the confidence interval for the estimated treatment difference and the type-III error.

Keywords

Error Probability Treatment Difference Large Clinical Trial Pragmatic Trial Small Clinical Trial 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin · Heidelberg 1988

Authors and Affiliations

  • K. D. MacRae
    • 1
  1. 1.Charing Cross and Westminster Medical SchoolLondonGreat Britain

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