A recent study investigated the extent to which hypertension is affected by alcohol consumption. Among other things, the study c
ompared the rate of hypertension in nondrinkers to the rate in people that are moderate beer drinkers (average between 0.5 and 1 glass of beer per day). They found that a 95% confidence interval for the relative risk of hypertension in moderate beer drinkers as compared to nondrinkers was 0.47 to 0.90. A relative risk of 1 means that the two groups have the same risk of hypertension, while a relative risk of less than 1 means that moderate beer drinkers have less risk of hypertension than nondrinkers. If the researchers who ran the study had tested the hypotheses.H0: the relative risk for moderate beer drinkers as compared to nondrinkers = 1 Ha: the relative risk for moderate beer drinkers as compared to nondrinkers ≠ 1
they would have concluded which of the following?
a) reject H0
b) fail to reject H0 at level 0.10
c) Neither choice is correct. We cannot determine what we would do at level a = 0.10 because the interval given is a 95% confidence interval, not a 90% confidence interval.
H0: the relative risk for moderate beer drinkers as compared to nondrinkers = 1
Ha: the relative risk for moderate beer drinkers as compared to nondrinkers ≠ 1
The level of significance, α = 0.1
Since the confidence interval for the relative risk of hypertension in moderate beer drinkers as compared to nondrinkers (0.47 to 0.90) does not contain the relative risk of 1, the null hypothesis will be rejected at the specified level of significance, 0.1. Therefore, the conclusion is to reject H0.
