quantumliner wrote:
Doctor: Research shows that adolescents who listen to music on headphones on a regular basis are three times as likely to develop serious hearing loss as are adolescents who do not use headphones. Federal legislation that prohibits the sale of headphones to minors would help to reduce the prevalence of hearing loss among adolescents.
In assessing the doctor’s assertion, it would be most useful to know which of the following?
a. percentage of federal legislators who would vote for a bill that prohibits the sale of headphones to minors.
b. The number of adolescents who use headphones on a regular basis but do not suffer from hearing loss.
c. The extent to which other common adolescent behaviors contribute to hearing loss.
d. The percentage of parents who would refuse to purchase headphones for their adolescent children.
e. The difference in level of hearing loss between adults who have used headphones since adolescence and those who began using headphones as adults.
Responding to a pm:
Adolescents who use headphones regularly are 3 times as likely to develop hearing loss as those who do not.
Conclusion:Federal legislation prohibiting the sale of headphones to minors would help to reduce the prevalence of hearing loss among adolescents.
Note what the assertion is: A law prohibiting the sale to minors will reduce the prevalence of hearing loss. It says a law will help. We need to evaluate whether this law will help. Be careful - we DO NOT need to evaluate whether such a law can be passed or not. We need to figure out that if there is such a law, will it help. It is similar to a case of conditional conclusion which I have discussed here:
a. percentage of federal legislators who would vote for a bill that prohibits the sale of headphones to minors.
This is trying to evaluate whether such a law can be passed. The point is we don't have to evaluate that. We have to evaluate whether such a law can reduce the prevalence of hearing loss among adolescents. This is not the answer.
b. The number of adolescents who use headphones on a regular basis but do not suffer from hearing loss.
We are looking for a reduction in the number, whatever the current percentage may be. This is irrelevant.
c. The extent to which other common adolescent behaviors contribute to hearing loss.
Irrelevant. We want to reduce the number of hearing losses due to headphones. Other causes are irrelevant.
d. The percentage of parents who would refuse to purchase headphones for their adolescent children.
This will help us evaluate whether refusing sale to adolescents will actually curtail access to them. It will certainly help in evaluating whether our law will help the desired impact.
e. The difference in level of hearing loss between adults who have used headphones since adolescence and those who began using headphones as adults.
Irrelevant.
Answer (D)
How would the answer to D help us evaluate the success of the legislation? We would rather want to know the change in percentage of parents who would buy, isn't it?