In a study the researchers fail to detect a real difference between two treatments because the sample was too small. Which error has occurred?
Answer and explanation
Correct answer: C. Type II error
- Step 1: A false negative conclusion is a type II error.
- Step 2: Power is 1 minus the probability of a type II error, and a small sample reduces power.
Answer
Type II error.
Why not the others: Confounding: Confounding distorts the association but is not this error. Selection bias: Selection bias is about how participants were chosen. Type I error: Type I error is a false positive.
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