P-value
The probability of seeing a difference at least this large if the treatment actually did nothing. Below 0.05 (a 1 in 20 chance) is the conventional threshold for calling a result 'statistically significant'. It measures surprise, not importance.
A small p-value means the result would be unlikely under pure chance, but it does not measure how big or how clinically meaningful the effect is; a trivial benefit in a huge trial can have a tiny p-value while a large benefit in a small trial can miss significance. Trials with several endpoints or several interim looks must spend their 0.05 across them (hierarchical testing, alpha spending), which is why an endpoint can be 'nominally significant' yet not count formally. The confidence interval conveys the same information about significance while also showing the size of the effect, and is generally more useful.
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not linked directly; found by shared links- TermMedian survival
Shares Confidence interval, Reading a hazard ratio, Hazard ratio (HR).
- TermBlinded trial
Shares Randomised trial, Endpoint.
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Shares Randomised trial, Endpoint.