Non-inferiority Randomized Controlled Trials

Abstract

Clinical trialists may explore competing interventions, not to demonstrate the superiority of one over the other, but instead to determine if a new therapy that is less burdensome, costly, or with lower risks of harms is not substantially less effective than the existing standard of care. This type of study is called a non-inferiority trial. This chapter describes an approach to assessing the validity of non-inferiority trials, interpreting results, and applying their findings. Clinicians, in consultation with their patients, should determine whether the loss in effectiveness suggested by the upper boundary of the 95% CI associated with the treatment effect of the novel approach is acceptable, regardless of a specific trial’s non-inferiority threshold.