A researcher is conducting a study to determine the mean trough dosage of medica

Question

A researcher is conducting a study to determine the mean trough dosage of medication for a population. Assume a previous study was conducted for the same medication and the mean trough dose was found to be 490 mg with a standard deviation of 40 mg. If the researcher wants to be 95% confident the true mean trough dosage of the medication is within 10 mg of the true mean trough dosage, what sample size is needed if the study is predicted to have an 88% retention rate? A. n = 8 B. n = 55 C. n = 71 D. n = 50

Explanation / Answer

The correct option is B

Explanation:

Given that
= 40
E =10

At 95 % confidence level the z is

alpha = 1- 95% = 1-0.95 = 0.05
alpha/2 = 0.05/2 =0.025

Z /2 =Z 0.025 =1.96

n =(Z /2 * /E)^2

n = (1.96 *40 /10)^2

n = 61.46

we have 88 % rention rate = 62*0.88 = 54.56 =55

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

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