We thank Dr. Sethuraman1 for their interest in our article2 and the opportunity to address their study design points. First, there was a concern that a non-inferiority design is only suitable for clinical trials in which a treatment or intervention is being compared to another (usually previously existing and well established as effective) treatment. While these types of studies were indeed early examples of noninferiority trials, application of this type of design has expanded rapidly in the last decade.3 From a statistical standpoint, it is possible to use a noninferiority design any time two continuous variables are being compared when one is expected to be “not different” (if double-sided) or either not higher or not lower (if single-sided) than the other.
In our study, we hypothesized that the gastric volume of diabetic patients who have followed standard fasting instructions prior to elective surgery would be “no higher”...