Please explain using excel worksheet and indicate formulas in the explanation. T
ID: 3238974 • Letter: P
Question
Please explain using excel worksheet and indicate formulas in the explanation. Thank you.
A clinical trial is being planned to investigate the effect of a new experimental drug designed to reduce total serum cholesterol. Investigators will enroll participants with total cholesterol levels between 200-240, they will be randomized to receive the new drug or a placebo and followed for 2 months, and the total cholesterol will be measured. Investigators plan to run a test of hypothesis and want 80% power to detect a difference of 10 points in mean total cholesterol levels between groups. They assume that 10% of the participants randomized will be lost over the 2 month follow-up. Assume that the standard deviation of total cholesterol is 18.5.
1. Suppose that there are 63 boys assigned to the new drug group and 58 boys assigned to the placebo. Is there a statistically significant difference in the proportions of boys assigned to the treatments? Run the appropriate test at a 5% level of significance.
Explanation / Answer
1.
P1 = 63/121 = 0.5207
std1 = 0.04542
P2 = 58/121 = 0.4793
std2 = 0.04542
z = (0.5207-0.4793)/(sqrt(2)*0.04542)
=0.6445<Za = 1.96
Reject null hypothesis because 6.67 >1.96 (Z-Value)