In this study, the analysis techniques used included intent to treat analysis, interim analysis and the use of statistical tests such as Students t-test to compare the two groups. The appropriateness of each of these tests and their relevance and applicability in this study setting is discussed below.
By definition, non inferiority trails are trials which aim at demonstrating that a new treatment modality or intervention is not inferior to the existing standard of care in terms of its efficacy and safety profile (Snapinn, 2000).Studies have revealed that the most appropriate statistical analysis techniques to be used for non-inferiority trails are intent-to-treat analysis (ITT) and per-protocol (PP) analysis, and there is an ongoing debate over which of the aforementioned analysis techniques is more suitable (D’Agostino, Massaro, & Sullivan, 2003). While patients are analyzed in the groups they had been assigned to at the beginning of the study, in an intent-to-treat analysis (ITT), irrespective of whether they completed the entire course of treatment or not, per-protocol analysis only includes patients who completed the entire course of the assigned treatment. Thus ITT is considered to be more liberal than PP analysis (D’Agostino, Massaro, & Sullivan, 2003).
Current recommendations advocate the concurrent use of both these approaches for data analysis in non-inferiority trials and if both approaches support non-inferiority, then the treatment modality or intervention is accepted as being non-inferior to the existing standard of care. In this study, the authors have used intent to treat analysis which is a suitable form of analysis for the study design used (Snapinn, 2000). However, if they used PP analysis simultaneously and that too proved non-inferiority, the strength of the study and the validity of the findings would have been greater.
Moreover, in this study, the analysis ...