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Intermediate Technical IVT

P-value

A statistical measure indicating the probability that observed results occurred by chance, with P<0.05 typically considered statistically significant.

Full Definition

The P-value represents the probability of obtaining results at least as extreme as those observed, assuming the null hypothesis is true. In cardiovascular research, P-values are crucial for determining statistical significance of treatment effects, with conventional thresholds of P<0.05 for significance and P<0.01 for high significance. Multiple comparison adjustments (such as Bonferroni correction) may be applied when testing numerous endpoints. Cardiovascular trials increasingly emphasize clinical significance alongside statistical significance, particularly for composite endpoints like MACE. Proper interpretation requires understanding of confidence intervals, effect sizes, and study power.

Usage

Usage note: Always italicize the 'P' in P-value; specify exact values rather than P<0.05 when possible.

In Context

  • "The primary endpoint achieved statistical significance with P=0.003 favoring the intervention group." — Clinical trial results
  • "After Bonferroni correction for multiple comparisons, the P-value threshold was adjusted to 0.0125." — Statistical analysis plan

Also known as

probability value significance level

Don't confuse with

confidence interval power

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