What is Non-inferiority trial (NI)NI is designed to see whether a new test agent is Not Unacceptably less efficacious than a standard treatment with well-established historical data.With continuous updates in primary studies and clinical uses,incremental benefits of newly developed treatments may be marginal over current treatments.To design another 3-arms RCT of new test agent to a standard treatment,as well as,placebo group may be unethical and a waste of resources.In such circumstances,there has been increasing use of NIs.NIs are more complex to design,conduct,and interpret than traditional superiority trials.Lets illustrate with a 3-arms diagram below.