P-Value — What It Means in Clinical Trials

Plain English Definition

A p-value is a number that tells you how likely it is that the trial's results happened by chance. A small p-value (typically less than 0.05) means the results are probably real, not random. A p-value of 0.05 means there is only a 5% probability the results are due to chance. The smaller the p-value, the stronger the evidence.

Why It Matters

You will see p-values in trial results. A p-value less than 0.05 is generally considered statistically significant. But remember — a p-value tells you about the probability of chance, not about how big or important the treatment effect is.

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