Please no guessing! Condfident answers only! A pharmaceutical company conducts a
randomized controlled trial to determine the efficacy of a newly developed topical solution for
inducing hair growth in men with male pattern baldness. Company researchers decide that
average hair count must increase by at least 20% in the drug-treated group, compared to the
placebo group, to be considered a clinically meaningful difference. They select a sample size that
will ensure 80% power for the statistical test, and carry out this test at the 5% level of
significance. Which of the following statements best describes alpha, the level of significance?
If average hair growth differs between the groups, the chance that the statistical test will detect a
significant difference between the groups is at least 95%. If average hair growth does not differ
between the groups, the chance of detecting a statistically significant difference between the
groups in terms of hair growth is 5% or less. The chance of detecting a statistically significant
difference between the groups is 95%. A statistically significant result will be obtained 5% of
the time that a true difference exists between the groups. None of these.
Solution
Answer: d.
Please no guessing! Condfident answers only! A pharmaceu.pdf
1. Please no guessing! Condfident answers only! A pharmaceutical company conducts a
randomized controlled trial to determine the efficacy of a newly developed topical solution for
inducing hair growth in men with male pattern baldness. Company researchers decide that
average hair count must increase by at least 20% in the drug-treated group, compared to the
placebo group, to be considered a clinically meaningful difference. They select a sample size that
will ensure 80% power for the statistical test, and carry out this test at the 5% level of
significance. Which of the following statements best describes alpha, the level of significance?
If average hair growth differs between the groups, the chance that the statistical test will detect a
significant difference between the groups is at least 95%. If average hair growth does not differ
between the groups, the chance of detecting a statistically significant difference between the
groups in terms of hair growth is 5% or less. The chance of detecting a statistically significant
difference between the groups is 95%. A statistically significant result will be obtained 5% of
the time that a true difference exists between the groups. None of these.
Solution
Answer: d
