Per-Protocol — What It Means in Clinical Trials

Plain English Definition

A per-protocol analysis only includes participants who completed the trial exactly as planned — taking every dose, attending every visit, and not violating any protocol rules. It excludes people who dropped out, missed doses, or deviated from the plan. This gives a best-case-scenario view of the treatment.

Why It Matters

Per-protocol results may look better than intent-to-treat results because they only count the "ideal" participants. Always compare both analyses to get a balanced view of how the treatment performs.

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