Table 1 Commonly used terminology in statistics of randomized controlled trials
Term | Explanation |
|---|---|
Null hypothesis | Claims that there is no difference in outcome across two or more groups (e.g., drug A is as good as placebo) |
Alternative hypothesis | Claims that there is a difference in outcome across two or more groups (e.g., drug A is better than placebo) |
Type 1 error (α) | Rejection of a true null hypothesis (i.e., a false-positive result) |
Type 2 error (β) | Failure to reject a false null hypothesis (i.e., a false-negative result) |
Effect size | A quantitative measure of the magnitude of the effect (e.g., mean difference, relative risk, or odds ratio) |
p value | Probability of obtaining the identified result (or something more extreme) under the assumption that the null hypothesis is true |