A placebo-controlled clinical study was done by a research team to see whether a novel medicine for treating acute migraine with or without aura in adults is more effective than usual treatment. In the trial, 3,500 individuals with acute migraine were randomly allocated to either the novel medicine or usual therapy. The researchers opt to set alpha to 0.01 rather than 0.05 during the data analysis phase. Which of the following outcomes is most likely as a result of this change?

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Eductional Objective: The significance level alpha (a) is used to determine the statistical significance of study results. It is typically set by investigators as the threshold for rejecting a null hypothesis (H0). When the p-value (ie, the likelihood of receiving outcomes as severe as the actual results when H0 is true) is less than the significance level (ie, p-value), the results of a research are considered statistically significant. Alpha also represents the likelihood of committing a type I mistake, which is rejecting a genuine H0 (ie, a false positive: finding a statistically significant difference when one does not truly exist).  The confidence level (1-a) is the counterpart of alpha/significance level, and it denotes the chance of not rejecting a true H0 (ie, a true negative, or not finding a statistically significant difference when one does not truly exist).
The lower the significance threshold, the less likely a type I mistake. This, however, means that the bar for statistical significance is higher.  As a result, decreasing the significance threshold (e.g., from a = 5% to a = 1%) reduces the likelihood of a type I error as well as the likelihood of detecting statistical significance (e.g., p-value 0.05 to p-value 0.01).   A lower significance level also implies a higher confidence level (1-a); thus, any statistically significant findings can be reported with greater certainty.

A Placebo-Controlled Clinical Study Was Done by a Research Team