Intent-to-Treat — What It Means in Clinical Trials
Plain English Definition
Intent-to-treat (ITT) analysis includes every participant who was randomized in the trial, regardless of whether they completed the treatment, dropped out, or switched groups. This approach gives the most realistic picture of how the treatment works in the real world, where not everyone finishes their prescribed course.
Why It Matters
ITT analysis is considered more trustworthy because it reflects reality. In the real world, some patients stop treatment due to side effects, and ITT captures that. Per-protocol analysis may make results look better than they actually are.
Example
A trial might note: "Primary analysis was conducted in the intent-to-treat population (N=500)." All 500 randomized participants are included, even those who stopped treatment early.
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