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Review
. 2019 Aug;19(8):267-271.
doi: 10.1016/j.bjae.2019.03.004. Epub 2019 Apr 24.

Non-inferiority statistics and equivalence studies

J Walker  1
Affiliations
Review

Non-inferiority statistics and equivalence studies

J Walker. BJA Educ. 2019 Aug.
No abstract available

PubMed Disclaimer

Conflict of interest statement

The author declares that they have no conflict of interest.

Figures

Fig. 1
Fig. 1
Traditional statistical tests, represented as 95% confidence intervals. The vertical line at 0 represents no difference, which is the null hypothesis. In situation A (blue), there is a statistically significant difference between the two treatments. In B (green) and C (red), there is no significant difference. However this cannot be taken as evidence of similarity, as ‘no difference’ is only one of a range of values the result can take.
Fig. 2
Fig. 2
Possible outcomes in a non-inferiority trial. In A (blue), non-inferiority is demonstrated. In B (green), non-inferiority is not demonstrated, and the trial is inconclusive. In C (red), the new treatment is inferior.
Fig. 3
Fig. 3
Possible outcomes during an equivalence trial. Drug A would be considered equivalent to the active control; in drugs B and C equivalence has not been shown.
See this image and copyright information in PMC

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