Question

16. (18.29) The placebo effect is particularly strong in patients with Parkinson's disease. To understand the workings of the placebo effect, scientists measure activity at a key point in the brain when patients receive a placebo that they think is an active drug and also when ne treatment is given. The same s pacients are measured both with and without the placebo, at different times. eBook Step 1: Explain why the proper procedure to compare the mean response to placebo with control (no treatment) is a matched pairs test. The proper procedure is a matched pairs t test because scientists measure activity at a key point in the brain. The proper procedure is a matched pairsttest because the same s patients are measured both with and without the placebo at different times. The proper procedure is a matched pairs test because the placebo effect is particularly strong in patients with Parkinson's disease The proper procedure is a matched pairs t test because there are exactly two groups. placebo and no treatment 0.181. Is there significant evidence of a difference between treatment and control? Step 2: The six differences (treatment minus control) had x = -0.326 and Yes, there is (0.025<P<0.05). Yes, there is (0.01 <P < 0.025). No, there isn't (P >0.05), Yes, there is (P < 0.01),

Answer 1

The proper procedure is a matched pairs t test because the same six patients are measured both with and without the placebo at di Herent times. © test Statistic, te X - U - s/n -0.326-O 0.18 VJ6 = -4.41178 df = 6-1 = 5 P-value = 2P(t <-4.41178) = 0.0069 → Yes, there is (P<0.01)