Question

In a clinical trial of Lipitor, a common drug used to lower cholesterol, 863 patients were given a treatment of 10-mg Atorvastatin tablets. Among them, 19 patients experienced flu symptoms and 844 patients did not.

a) Estimate the probability that a patient taking the drug will experience flu symptoms.

b) Is this unusual for a patient taking the drug to experience flu symptoms? Explain.

c) If you know that the probability of flu symptoms for a person not receiving any treatment is 0.019, what is the probability that there are 19 who experience flu symptoms among 863 patients? Explain.

d) Is this unusual to find that among 863 patients, there are 19 who experience flu symptoms in c)? Explain.

Answer 1

(A) Probability that a patient taking the drug will experience flu symptoms= (number of patient taking drug)/(total patients)

= 19/863

= 0.0220

(B) Yes, it is unusual because the probability that a patient taking the drug will experience flu symptoms is less than 0.05. So, it is an unusual probability

(C) it is given that p = 0.019, total sample size n = 863 and k = 19 (selection)

using binomial function binompdf(n,p,k)

= binompdf(863, 0.019,19)

= 0.0754

Therefore, probability that there are 19 who experience flu symptoms among 863 patients is 0.0754

(D) It is not unusual because the calculated probability is more than 0.05. Therefore, the probability that there are 19 who experience flu symptoms among 863 patients is not unusual