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Intermediate Technical IVT

per-protocol analysis

A statistical analysis method that includes only participants who completed the study according to the protocol requirements, excluding protocol violations and non-compliant subjects.

Full Definition

Per-protocol (PP) analysis is a complementary analytical approach to intention-to-treat analysis that restricts the analysis population to participants who adhered to the study protocol as planned. This includes patients who received the allocated intervention, had adequate compliance with study procedures, and completed follow-up without major protocol deviations. While per-protocol analysis can provide insights into treatment efficacy under ideal conditions, it may introduce bias by excluding patients with poor outcomes who discontinued treatment. In cardiovascular research, per-protocol analyses are particularly useful for understanding the biological effect of interventions when taken as prescribed.

Usage

Usage note: Hyphenate as 'per-protocol analysis' rather than 'per protocol analysis' for consistency with statistical guidelines.

In Context

  • "Both intention-to-treat and per-protocol analyses demonstrated consistent treatment benefits." — Statistical analysis section
  • "The per-protocol population excluded 127 patients due to major protocol deviations or poor compliance." — Study flow diagram

Also known as

PP analysis on-treatment analysis

Contrasted with

intention-to-treat analysis

Don't confuse with

as-treated analysis ITT analysis

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