What does Intention-to-Treat (ITT) analysis involve?

Intention-to-Treat (ITT) analysis is a statistical approach that focuses on including all participants in the groups to which they were originally assigned, regardless of whether they completed the study or adhered to the treatment protocol. This method is critically important because it helps to maintain the randomization benefits of the original trial and reduces bias. By analyzing participants based on their initial group assignments, ITT preserves the integrity of the randomization process, providing a more accurate reflection of the treatment effect in a real-world scenario.

This approach acknowledges that in practical applications, not all participants will follow the study protocol perfectly, but this should not invalidate their contributions to the findings. By incorporating all participants, ITT analysis provides a comprehensive evaluation of the intervention's impact, even when considering issues such as dropout rates and noncompliance. This is key to ensuring the results are generalizable and reflective of typical clinical practice, where not all patients follow the prescribed treatment regimen.

The other choices focus on limiting the analysis based on completion, compliance, or demographic factors, which would compromise the integrity and intent of the research.