Study design
Non-inferiority trial
A trial designed to test whether a new intervention is not unacceptably worse than a comparator.
What it means
Definition
Non-inferiority trial. Non-inferiority trials are useful when a new option may be cheaper, safer or easier. Interpretation depends on the pre-specified margin and whether the comparator was effective and used properly.
What it can tell you
It can show how close the evidence is to a real human health outcome.
What it cannot tell you
It cannot prove that a treatment works in people unless human outcome data are available.
Headline trap
Why this matters in headlines
A “just as good” headline needs scrutiny of the non-inferiority margin.