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I would like to share the two definitions given in two separate endgames as defined by Dr. Sedgwick:
The P value represents the proportion of the theoretical infinite number of samples—that is, 0.449 (44.9%)—that have a mean difference in birth weight equal to, or greater than, that observed in the trial above (Understanding p-value)1.
The percentage of these repeated samples that would demonstrate the smallest effect of clinical interest (if it existed in the population) as a significant difference (P<0.05) is the statistical power of the calculated sample size in the above trial (The importance of statistical power)2.
Comparing the two definitions may clarify the difference in the two, my confusion is cleared.
The p-value and statistical power as defined in two endgames
I would like to share the two definitions given in two separate endgames as defined by Dr. Sedgwick:
The P value represents the proportion of the theoretical infinite number of samples—that is, 0.449 (44.9%)—that have a mean difference in birth weight equal to, or greater than, that observed in the trial above (Understanding p-value)1.
The percentage of these repeated samples that would demonstrate the smallest effect of clinical interest (if it existed in the population) as a significant difference (P<0.05) is the statistical power of the calculated sample size in the above trial (The importance of statistical power)2.
Comparing the two definitions may clarify the difference in the two, my confusion is cleared.
References:
1. BMJ 2014;349:g4550
2. BMJ 2013;347:f6282
Competing interests: No competing interests