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A Clinical Trial Assessing the Safety, Efficacy, and Delivery of Olive-Oil-Based Three-Chamber Bags for Parenteral Nutrition
Published on: September 20, 2019
Hypothesis testing in clinical trials
1Department of Epidemiology and Biostatistics, School of Medicine, Case Western Reserve University, Cleveland, Ohio, USA.
Abstract:
In designing and analyzing any clinical trial, two issues related to patient heterogeneity must be considered: (1) the effect of chance and (2) the effect of bias. These issues are addressed by enrolling adequate numbers of patients in the study and using randomization for treatment assignment. An "intention-to-treat" analysis of outcome data includes all individuals randomized and counted in the group to which they are randomized. There is an increased risk of spurious results with a greater number of subgroup analyses, particularly when these analyses are data derived. Factorial designs are sometimes appropriate and can lead to efficiencies by addressing more than one comparison of interventions in a single trial.
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