The placebo effect. The placebo effect is particularly strong in patients with P

Question

The placebo effect. 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 no treatment is given.22 The same 6 patients are measured both with and with' out the placebo, at different times. Explain why the proper procedure to compare the mean response to placebo with that to control (no treatment) is a matched pairs t test. The six differences (treatment minus control) had x bar = -0.326 and s = 0.181. Is there significant evidence of a difference between treatment and control?

Explanation / Answer

a) In the given problem, paired data has been collected ( 6 pair sof patients received, placebo and no control treatments) and the results are then matched to compute test statistic.

b) From information given,

n=6 pairs, dbar=-0.326, sd=0.181

t5=(dbar-0)/SE(dbar)=-0.326/(0.181/sqrt 6)=-4.411

The p value is 0.00695, and is less than 0.05. Therefore, reject null hypothesis to conclude that there exists significant differnce between treatment and control.

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.