Equivalence design

Deze pagina lezen in het Nederlands.

This page was translated from the Dutch-language original using AI and has not been fully reviewed. Where the two differ, the Dutch version takes precedence.

Contents

• What is the difference between a regular test and a test for equivalence?
• I have tested a one-sided hypothesis, how should I report my confidence interval around the effect measure?
• We are conducting a randomized trial with a non-inferiority hypothesis. How do I choose the population for this analysis?
• References

What is the difference between a regular test and a test for equivalence?

The difference briefly comes down to the following. In a regular (superiority) test, the null hypothesis is 'no difference' and the alternative hypothesis is 'a difference exists'. A small p-value points towards the alternative hypothesis and thus indicates a difference (e.g. between groups). In an equivalence test, the null hypothesis is that there is in fact a difference (what counts as a difference is determined by the equivalence margin). The alternative hypothesis is that there is no difference. A small p-value points towards the alternative hypothesis, thus indicating equivalence (no difference between groups).

I have tested a one-sided hypothesis, how should I report my confidence interval around the effect measure?

See this GraphPad Prism help file for a detailed explanation.

We are conducting a randomized trial with a non-inferiority hypothesis. How do I choose the population for this analysis?

In the case of a non-inferiority hypothesis - in contrast to superiority studies - the intention-to-treat set is not the 'conservative' approach. In the case of non-adherence, the contrast between the two groups is diluted. This (incorrectly) increases the probability of confirming non-inferiority. This problem and possible solutions are clearly explained in this paper (Mo et al. 2020).

References

• Lesaffre E, Superiority, Equivalence, and Non-Inferiority Trials. Bulletin of the NYU Hospital for Joint Diseases 2008;66(2):150-4

• William C. Blackwelder. Proving the null hypothesis in clinical trials, Controlled Clinical Trials, Volume 3, Issue 4, December 1982, Pages 345-353

• B. Jones, P. Jarvis, J. A. Lewis, and A. F. Ebbutt, Trials to assess equivalence: the importance of rigorous methods, BMJ. 1996 July 6; 313(7048): 36–39

• Temple R., Ellenberg S, Placebo-controlled trials and active-control trials in the evaluation of new treatments. Part 1: Ethical and Scientific Issues, Ann Intern Med. 2000 Sep 19;133(6):455-63

• Ellenberg SS, Temple R., Placebo-controlled trials and active-control trials in the evaluation of new treatments. Part 2: practical issues and specific cases, Ann Intern Med. 2000 Sep 19;133(6):464-70

• Guideline on the choice of the non-inferiority margin(CHMP), EMEA/CPMP/EWP/2158/99 July 2005

• S.J. Pocock, The pros and cons of noninferiority trials, Fundamental & Clinical Pharmacology 17 (2003) 483–490

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