When the aim of the randomized controlled trial (RCT) is to show that one treatment is superior to another, a statistical test is employed and the trial (test) is called a superiority trial (test). Often a nonsignificant superiority test is wrongly interpreted as proof of no difference between the two treatments.
Can a superiority trial show non-inferiority?
When the results of the trial become available, they may suggest an alternative interpretation. Thus the results of a superiority trial may only appear to be sufficient to support non- inferiority , while the results of a non-inferiority trial may appear to support superiority.
What is the difference between a non-inferiority trial and a superiority trial?
In comparison studies with a current therapy, non-inferiority is used to demonstrate that the new therapy provides at least the same benefit to the patient . Superiority trials are always used when comparisons are made to placebo or vehicle treatments.
What is a Phase 3 superiority trial?
Most phase III trials in oncology aim to demonstrate the superiority of a new treatment in comparison with control , but so-called non-inferiority phase III trials assess whether a more convenient, less toxic, or more affordable intervention is at least as efficacious as an existing standard of care.
What is an inferiority trial?
Active control trials aim to demonstrate that treatments of interest have either superior effects or similar effects to the control. ... If the intent of a study is to demonstrate that an experimental treatment is not substantially worse than a control treatment , the study is known as a noninferiority trial.
What is the null hypothesis for superiority trial?
The null hypothesis (H 0 ) of superiority trials asserts that there is no true difference between the interventions , and the alternative hypothesis (H 1 ) states that there is a difference between the interventions. A type I error is the error of rejecting H 0 when it is actually true.
What does a non-inferiority trial mean?
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.
What is a good non-inferiority margin?
In order to demonstrate non-inferiority, the recommended approach is to pre-specify a margin of non- inferiority in the protocol. After study completion, a two-sided 95% confidence interval (or one-sided 97.5% interval) for the true difference between the two agents will be constructed.
What phase is a non-inferiority trial?
Non-inferiority (NI) trials in drug research are used to demonstrate that a new treatment is not less effective than an active comparator. Since phase IV trials typically aim at informing a clinical decision, the value of a phase IV non-inferiority trial hinges also on its clinical relevance.
What is the null hypothesis for a non-inferiority trial?
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.
How do you do a non-inferiority test?
In noninferiority testing, a common practice is to set the value of δ to a fraction, f, of the lower limit of a confidence interval of the difference between the current therapy and the placebo obtained from a meta-analysis.
What is a non superiority trial?
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 equivalent trial?
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.
What is inferiority margin?
Abstract. Noninferiority trials are used to assess whether the effect of a new drug is not worse than an active comparator by more than a noninferiority margin. If the difference between the new drug and the active comparator does not exceed this prespecified margin, noninferiority can be concluded.
What do you mean by inferiority?
noun. the quality or state of being lesser or lower in rank, position, quality, etc .:Negative perceptions about the inferiority of generic drugs compared to brand name drugs were more pronounced among some segments of the studied population.
What is a pragmatic trial design?
Pragmatic trials are designed to evaluate the effectiveness of interventions in real-life routine practice conditions , whereas explanatory trials aim to test whether an intervention works under optimal situations. Pragmatic trials produce results that can be generalized and applied in routine practice settings.
