What does a p-value of 0.03 mean in a randomised trial?
Answer and explanation
Correct answer: C. A result at least this extreme would occur about 3 percent of the time under no true difference
- Step 1: The p-value is a conditional probability assuming the null hypothesis.
- Step 2: It is the probability of data at least this extreme if the null hypothesis were true, not a probability that a hypothesis is true.
Answer
A result at least this extreme would occur about 3 percent of the time under no true difference.
Why not the others: The effect is clinically important: Statistical significance does not show clinical importance. There is a 3 percent probability that the null hypothesis is true: It is not the probability that the null is true. There is a 97 percent probability that the treatment works: It is not the probability that the treatment works.
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