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Intermediate Technical IVT

primary endpoint

The main outcome measure in a clinical trial, used to determine sample size and assess treatment efficacy.

Full Definition

The primary endpoint is the most important outcome measure in a cardiovascular clinical trial, predetermined during study design to evaluate the intervention's primary effect. It serves as the basis for sample size calculations, statistical power determination, and regulatory approval decisions. In cardiovascular research, primary endpoints may include major adverse cardiovascular events (MACE), mortality, hospitalization rates, or procedural success metrics. The choice of primary endpoint significantly impacts trial design, duration, and interpretation of results. Regulatory agencies typically require demonstration of benefit on the primary endpoint for drug or device approval.

Usage

Usage note: Always specify timing (e.g., '30-day primary endpoint') and clearly distinguish from secondary endpoints.

In Context

  • "The primary endpoint was achieved by 8.5% of patients in the treatment group versus 12.1% in the control group." — clinical trial results
  • "Cardiovascular death was selected as the primary endpoint for this outcomes trial." — study protocol

Also known as

primary outcome main endpoint

Contrasted with

secondary endpoint

Don't confuse with

primary vs secondary endpoint endpoint vs outcome

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