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A review of sample size determination in randomised controlled studies

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Author Affiliations

  • 1Nigerian Institute of Medical Research, 6 Edmund Crescent, P.M.B. 2013, Yaba, Lagos, Nigeria
  • 2Nigerian Institute of Medical Research, 6 Edmund Crescent, P.M.B. 2013, Yaba, Lagos, Nigeria
  • 3Nigerian Institute of Medical Research, 6 Edmund Crescent, P.M.B. 2013, Yaba, Lagos, Nigeria

Res. J. Mathematical & Statistical Sci., Volume 11, Issue (1), Pages 9-14, May,12 (2023)

Abstract

This review discusses some statistical concepts relevant to understanding and estimating sample size for randomised controlled trials (RCTs). A RCT is still the best way to compare the effects of treatments. This concept is illustrated with illustrative examples of equivalence, non-inferiority and superiority RCTs. The RCTs can be designed and conducted as superiority studies. Randomised clinical trials can be used in establishing that a proposed intervention is equivalent or noninferior to standard therapy rather than superior, meaning that the trials can be conducted as such studies. This research differs significantly in several methodological aspects because they focus on different goals. To be honest, awareness of the differences in clinical trial methodologies is often limited. This paper provides an overview of the methodology of this type of research which includes planning, execution, analysis, and reporting of trial. We hope that review article of this nature will be useful to biomedical researchers and other scientists in estimating sample sizes for studies in their various disciplines.

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