Is non-inferiority the same as equivalence?
Non-inferiority trials aim to show that the new drug is no worse than standard treatment. Equivalence trials aim to show the new treatment is no better and no worse. An equivalence boundary should be set before the trial. This is the definition of what would be the minimum important difference between the treatments.
What is a non-inferiority analysis?
A study that tests whether a new treatment is not worse than an active treatment it is being compared to. Non-inferiority trials are sometimes done when a placebo (an inactive treatment) cannot be used.
What is non-inferiority?
By definition, a non-inferiority trial aims to demonstrate that the test product is not worse than the comparator by more than a small pre-specified amount. This amount is known as the non-inferiority margin, or delta. Clinicians must know who has chosen the margin, and why.
What is the difference between superiority and non-inferiority?
Introduction. Unlike superiority trials that are designed to show that one treatment is better than another, a non-inferiority trial is designed to show that a new treatment is ‘not unacceptably worse’ than the current standard therapy.
What is an equivalence study?
In an equivalence trial, the statistical test aims at showing that two treatments are not too different in characteristics, where “not too different” is defined in a clinical manner. Finally, in a non-inferiority trial, the aim is to show that an experimental treatment is not (much) worse than a standard treatment.
How does testing for non-inferiority test for equivalence?
Non-inferiority is shown if the lower side of a two-sided (1–2α)×100% CI is above -Δ. In this case that means a 95 % CI, so the significance level is 0.025. Using the two one-sided test (TOST) procedure, equivalence is tested using a (1–2α)×100% CI. In this case this significance level is also 0.025.
What is the null hypothesis in a non-inferiority study?
The null hypothesis in non-inferiority trials is that new treatment is inferior to standard treatment. The alternative hypothesis is the new treatment is non-inferior to standard treatment.
What does non inferior mean?
Abstract. As clinicians, we are frequently faced with papers stating that something is ‘non-inferior’ to something else. By definition, a non-inferiority trial aims to demonstrate that the test product is not worse than the comparator by more than a small pre-specified amount.
What is non-inferiority and superiority?
Unlike superiority trials that are designed to show that one treatment is better than another, a non-inferiority trial is designed to show that a new treatment is ‘not unacceptably worse’ than the current standard therapy.
How do you perform an equivalence test?
This is done by conducting two one-sided t-tests, each of which is based on a null hypothesis that is one of the parts of the above null hypothesis. If the null hypothesis of both tests is rejected then the difference falls within the equivalence interval and you can claim that the two population means are equivalent.
How do you calculate non-inferiority margin?
The margin represents the remaining fraction of M1, which is called M2. For example, if it is decided that 75% of M1 must be preserved by the new drug to demonstrate noninferiority, M2 = (1 – 0.75) × M1 = 0.25 × M1 (or 25% of M1) 2, 3.
How do you do an equivalence test in Excel?
Run an Equivalence-Test Using QI Macros Select the data within your Excel spreadsheet, click on QI Macros menu, Statistical Tools and select Equivalence test.
What is equivalence limit?
Defining Equivalence Limits: Your Call The lower equivalence limit (LEL) defines your lower limit of acceptability for the difference. The upper equivalence limit (UEL) defines your upper limit of acceptability for the difference. Any difference from the mean that falls within this zone is considered unimportant.
How do you interpret non-inferiority margins?
The calculated CI does not know whether its purpose is to judge superiority or non-inferiority. If it sits wholly above zero, then it has shown superiority. If it sits wholly above -Δ, then it has shown non-inferiority. A non-inferiority trial can have five possible types of outcomes as depicted in Figure 2.
How is statistical equivalence calculated?
When using equivalence tests, we must specify how large of a difference between the group averages would represent a practically important difference. Then, smaller differences than that are considered insignificant when comparing the group averages and equivalence may be concluded.
How do you test equivalence?
How do you establish an equivalence?
Demonstrating equivalence requires defining a difference Δ that is considered significant and then demonstrating with high confidence the difference is less than Δ. Equivalence tests are based on confidence intervals.