Question 2: What is meant by ‘two-sided level of significance at 0.05’ and why did they need to specify this?’
This means that a difference would be regarded as statistically significant, and so would provide evidence of a treatment effect, if the difference observed were such that the proportion of samples which would produce a difference as large as or larger than that observed, in either direction, was 0.05 or less. They set this as the level of evidence which would enable them to conclude that defibrotide is different from the control treatment.
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Last updated: 3 February, 2020.