# How do you calculate non-inferiority?

## How do you calculate non-inferiority?

To calculate the sample size, we can use Table 5, which gives calculated sample sizes for various standardised non-inferiority limits (δNI = dNI/σ). The percentage mean differences are given for the case where it is anticipated that there may be a non-zero difference between treatments, that is, µA−µB = 0.

**What does non inferior mean in statistics?**

(… in-FEER-ee-OR-ih-tee TRY-ul) 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.

**How do you evaluate a non-inferiority trial?**

A non-inferiority trial should specify whether a one- or two-sided CI is placed around the estimate of difference between treatments. If a two-sided test is used, the 95% CI applies; if a one-sided test is used, the 97.5% CI applies. Use of more liberal 90% CIs should be viewed with caution.

### How do you interpret non-inferiority results?

If the upper bound of the 95% CI falls below the noninferiority margin, ƒ, then the trial has failed to demonstrate noninferiority and has in fact demonstrated inferiority (Figure 3). If the 95% CI crosses ƒ, then the study result is indeterminate.

**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 is the main difference between non-inferiority and equivalence trials conceptually and statistically?**

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 the difference between a non-inferiority trial and a superiority trial?

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 the null hypothesis in a non-inferiority trial?**

**What is the p value for non-inferiority?**

In non-inferiority trials, investigators are interested in whether new treatment is non-inferior to standard treatment. Only the non-inferior margin to the right side of unity on the forest plot is specified. Therefore, the significance level is usually set as a one-sided p value of 0.025.