An issue of Science News (Vol. 163, No. 22, pp. 341-342) reported that the Women’s Health initiative cast doubts on the benefit of hormone -replacement therapy. Researchers randomly divided 4532 healthy women over the age of 65 years into two groups. One group, consisting of 2229 women, received hormone-replacement therapy, the other group, consisting of 2303 women received placebo. Over 5 years, 40 of the women receiving the hormone -replacement therapy were diagnosed with dementia, compared with 21 of those getting placebo. b. Determine and interpret a 90% confidence interval for the difference in dementia risk rates for healthy women over 65 years old who take hormone -replacement therapy and those who do not.

An issue of Science News (Vol. 163, No. 22, pp. 341-342) reported that the Women’s Health initiative cast doubts on the benefit of hormone -replacement therapy. Researchers randomly divided 4532 healthy women over the age of 65 years into two groups. One group, consisting of 2229 women, received hormone-replacement therapy, the other group, consisting of 2303 women received placebo. Over 5 years, 40 of the women receiving the hormone -replacement therapy were diagnosed with dementia, compared with 21 of those getting placebo. b. Determine and interpret a 90% confidence interval for the difference in dementia risk rates for healthy women over 65 years old who take hormone -replacement therapy and those who do not.

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Holt Mcdougal Larson Pre-algebra: Student Edition 2012

1st Edition

ISBN:9780547587776

Author:HOLT MCDOUGAL

Publisher:HOLT MCDOUGAL

Chapter11: Data Analysis And Probability

Section: Chapter Questions

Problem 8CR

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Hormone Therapy and Dementia. An issue of Science News (Vol. 163, No. 22, pp. 341–342) reported that the Women’s Health Initiative cast doubts on the benefit of hormone-replacement therapy. Researchers randomly divided 4532 healthy women over the age of 65 years into two groups. One group, consisting of 2229 women, received hormone-replacement therapy; the other group, consisting of 2303 women, received placebo. Over 5 years, 40 of the women receiving the hormone-replacement therapy were diagnosed with dementia, compared with 21 of those getting placebo. a. At the 5% significance level, do the data provide sufficient evidence to conclude that healthy women over 65 years old who take hormone-replacement therapy are at greater risk for dementia than those who do not? b. Determine and interpret a 90% confidence interval for the difference in dementia risk rates for healthy women over 65 years old who take hormone-replacement therapy and those who do not.
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