[See] In a small clinical trial, 10 patients with chronic pain were randomly assigned to receive either drug A or drug B for one month. After completing


Question: In a small clinical trial, 10 patients with chronic pain were randomly assigned to receive either drug A or drug B for one month. After completing the month, they then had a two week "wash-out" period during which no drug was taken, and then received the alternative drug for one month. At the end of the study, they were asked to state which drug they preferred because it gave them greater relief from the pain. Each patient had to choose one drug. Eight patients said that they preferred drug A.

  1. If drug A and drug B were truly equal in their effects in reducing pain, what would be the probability that a patient expressed a preference for drug A over drug B?
  2. How many ways are there of obtaining 10 patients expressing a preference for drug A. Repeat for 9 patients, 8 patients,…1, 0 patients. Tabulate your results.
    (which is obtained using Excel’s COMBIN(10, k))
  3. What is the probability of having 8 patients express a preference for drug A if drugs A and B were truly equal in their effects? What is the probability of having 8 or more patients express a preference for drug A under the same condition? Show how these probabilities can be obtained from your table in part b)
    (where this probability is computed with the aid of Excel). As we can see, the number of ways to get k patients with a preference for drug A is used to compute the respective probabilities, together with the factor \({{0.5}^{10}}\), which is the specific probability of each way.
  4. Draw conclusions with regard to the finding that 8 patients preferred drug A. Give assumptions you have made in carrying out the above calculations and discuss their appropriateness.

Price: $2.99
Solution: The downloadable solution consists of 3 pages
Deliverable: Word Document

log in to your account

Don't have a membership account?
REGISTER

reset password

Back to
log in

sign up

Back to
log in