Question

a certain drug is used to treat asthma. in a clinical trial of the drug, 22 of 251 treated subjects experienced headaches (based on data from the manufacturer). the accompanying calculator display shows results from a test of the claim that less than 8% of treated subjects experienced headaches. use the normal distribution as an approximation to the binomial distribution and assume a 0.01 significance level to complete parts (a) through (e) below.
1 - propztest
prop < 0.08
z = 0.446709780
p = 0.6724576902
\hat{p}=0.0876494024
n = 251
a. is the test two - tailed, left - tailed, or right - tailed?
right tailed test
left - tailed test
two - tailed test

Explanation:

The claim is that less than 8% of treated subjects experienced headaches. In hypothesis testing, when the alternative hypothesis is of the form \(p < p_0\) (where \(p_0 = 0.08\) in this case), the test is left - tailed. The direction of the inequality in the alternative hypothesis determines the tail of the test.

Answer:

Left - tailed test