OBJECTIVE:NI margins have to be chosen appropriately to control the risk of degradation of treatment effects in non-inferiority (NI) trials. We aimed to study whether the current choice of NI margins protects sufficiently against a degradation of treatment effect on an average. STUDY DESIGN AND SETTING:NI trials reflecting current practice were assembled and for each trial. the NI mar... https://danddcollectiblers.shop/product-category/frame/