Intention to Treat
It has become commonplace for Randomized Controlled Trials (RCTs) to be analyzed according to Intention-to-Treat (ITT) principles in which data from all subjects are used regardless of the subjects' adherence to protocol.
While ITT analyses can provide useful information in some cases, they do not answer the question that motivates many RCTs, namely, whether the treatments differ in efficacy. ITT tends to reduce information by combining two questions, whether the intervention is effective and whether, as implemented, it has good compliance.
Because these questions may be separate there is a risk of misuse.
- Intention to Treat – What Is The Question?
R. Feinman, PhD, Nutrition & Metabolism, January 2009
- The Little Handbook of Statistical Practice Gerard E. Dallal, Ph.D
- Intention-To-Treat Analysis - Asking the Right Question Gerard E. Dallal, Ph.D.
- Study Design Exercises Gerard E. Dallal, Ph.D