Cardiovascular disease is a major cause of death and illness worldwide, with high blood pressure and high LDL cholesterol both being established risk factors. Because most cardiovascular events occur in persons with average risk and no previous cardiovascular disease history, the present research examined the simultaneous use of both blood pressure‑reducing drugs and cholesterol‑reducing drugs on this population rather than focus on only those at high risk.
Subjects included men at least 55 years old and women at least 65 years old without cardiovascular disease who had at least one additional risk factor besides age, such as recent or current smoking, hypertension, or family history of premature coronary heart disease. Those with current cardiovascular disease were excluded from the study. Subjects were randomly assigned to the treatment (cholesterol‑ and blood pressure‑reducing drugs) or a placebo, and the number suffering the primary outcome of a fatal cardiovascular
Group |
Number Experiencing Primary Outcome |
|
---|---|---|
Treatment | 3180 | 113 |
Placebo | 3168 | 157 |
How strong is the evidence that the proportion of subjects experiencing the primary outcome in the treatment group differs from that of those who were in the control group? Follow the four‑step process.
SOLVE: Calculate the sample proportions, ?̂ 1 and ?̂ 2,, and the pooled sample proportion, ?̂ . Give your answers to four decimal places.
Compute the test statistic ?. Give your answer to two decimal places.
Using Table A, find the
0.01<?<0.05
?<0.005
0.005<?<0.01
?>0.05
Step by stepSolved in 4 steps with 3 images
- Hyperhidrosis is a stressful medical condition characterized by chronic excessive sweating. Botox was approved for treatment of hyperhidrosis in adults in 2004. A clinical trial examined the effectiveness of Botox for excessive armpit sweating in teenagers aged 12 to 17 years. Participants received either a Botox injection or a placebo injection (a simple saline solution) and were examined four weeks later to see if their sweating had been reduced. Here are the study's findings: Botox Placebo Total Reduced Confidence Interval: 72 52 124 Not Reduced 28 We are 95% confident that there is hyperhidrosis who experienced a reduction in sweating. 148 176 Total 100 200 - Construct a 95% confidence interval for p₁ - P2 where p₁ denotes the proportion of teenagers who experienced a reduction in sweating in the Botox group and p2 denotes the proportion of teenagers who experienced a reduction in sweating in the placebo group. Round your answers to three decimal places, and use four decimal places…arrow_forwardSerum estradiol is an important risk factor for breast cancer in postmenopausal women. To better understand the etiology of breast cancer, serum-estradiol samples were collected from 25 premenopausal women (at about the same time period of the menstrual cycle) of whom 10 were Caucasian and 15 were African American. The data are shown in Table 7.3. The distribution of serum estradiol is usually highly skewed (especially for premenopausal women), and we are reluctant to assume normality. Table 7.3 Serum estradiol and ethnicity in 25 premenopausal women, where 0=Caucasian and 1=African-American ID Serum_estradiol Ethic 1 94 0 2 54 1 3 31 0 4 21 1 5 46 1 6 56 0 7 18 1 8 19 1 9 12 1 10 14 0 11 25 0 12 35 1 13 22 1 14 71 0 15 43 1 16 35 1 17 42 1 18 50 1 19 44 1 20 41 0 21 28 0 22 65 0 23 31 0 24…arrow_forwardA deficiency of the trace element selenium in the diet can negatively impact growth, immunity, muscle and neuromuscular function, and fertility. The introduction of selenium supplements to dairy cows is justified when pastures have low selenium levels. Authors of a research paper supplied the following data on milk selenium concentration (mg/L) for a sample of cows given a selenium supplement (the treatment group) and a control sample given no supplement, both initially and after a 9-day period. Initial Measurement Treatment Control 11.4 9.1 9.6 8.7 10.1 9.7 8.5 10.8 10.2 10.9 10.6 10.6 11.9 10.1 9.9 12.3 10.7 8.8 10.2 10.4 10.3 10.9 11.4 10.4 9.3 11.6 10.6 10.9 10.9 8.3 After 9 Days Treatment Control 138.3 9.2 104 8.9 96.4 8.9 89 10.1 88 9.6 103.8 8.6 147.3 10.4 97.1 12.4 172.6 9.2 146.3 9.5 99 8.4 122.3 8.8 103 12.5 117.8 9.1 121.5 93 (a) Use the given data for the treatment group to determine if…arrow_forward
- In a population-based cohort study, an entire community was interviewed regarding smoking habits and then followed for one year. Upon ascertainment of all lung cancer deaths, the investigator obtained the following data: Number of Individuals Lung Cancer Deaths Smokers 24,500 15 Nonsmokers 10,500 2 Calculate the risk difference per 100,000 per year. Round to the tenth decimaarrow_forwardSerum estradiol is an important risk factor for breast cancer in postmenopausal women. To better understand the etiology of breast cancer, serum-estradiol samples were collected from 25 premenopausal women (at about the same time period of the menstrual cycle) of whom 10 were Caucasian and 15 were African American. The data are shown in Table 7.3. The distribution of serum estradiol is usually highly skewed (especially for premenopausal women), and we are reluctant to assume normality. Table 7.3 Serum estradiol and ethnicity in 25 premenopausal women, where 0=Caucasian and 1=African-American. ID Serum_estradiol Ethic 1 94 0 2 54 1 3 31 0 4 21 1 5 46 1 6 56 0 7 18 1 8 19 1 9 12 1 10 14 0 11 25 0 12 35 1 13 22 1 14 71 0 15 43 1 16 35 1 17 42 1 18 50 1 19 44 1 20 41 0 21 28 0 22 65 0 23 31 0 24…arrow_forwardConsider a simple logistic model in which the response variable is attendance at a conference (yes = 1; no = 0), and the sole independent variable is a college degree (degree = 1; no degree = 0). The estimated odds ratio for the college degree variable is 1.25. What is its proper interpretation?arrow_forward
- The following is data about the hemoglobin concentrations of volunteers collected at sea level and at an altitude of 11000 feet. sea level concentrations = [14.70 , 15.22, 15.28, 16.58, 15.10 , 15.66, 15.91, 14.41, 14.73, 15.09, 15.62, 14.92]11000 feet concentrations = [14.81, 15.68, 15.57, 16.59, 15.21, 15.69, 16.16, 14.68, 15.09, 15.30 , 16.15, 14.76] There are two alternative scenarios about the way the data were obtained. In scenario 1, there are 12 volunteers who lived for a month at sea level, at which time blood was drawn and the data in "sea level concentrations" dataset were obtained. Subsequently, all 12 volunteers were moved to 11000 ft and after a month the data in the "11000 feet concentrations" dataset obtained. There is a one to one correspondence between the numbers in the two datasets, that is the first numbers correspond to volunteer1, the second numbers to volunteer2 etc. In scenario 2, the "sea level concentrations" dataset is a random sample obtained from 12…arrow_forwardMost cases of cervical cancer are linked to a few strains of the human papilloma virus (HPV). The pharmaceutical company Merck developed a vaccine (Gardisil) against these HPV strains. Worldwide clinical trials followed young women after vaccination or administration of placebo for two to four years for signs of HPV-caused cervical cancer. Based on a sample of 100 women in the Gardisil group, 24 % developed cervical cancer, and based on a sample of 100 women in the placebo group, 34 % developed cervical cancer. Test the claim that the proportion of women who developed cervical cancer in the Gardisil group is less than the proportion of women who developed cervical cancer in the placebo group at a = 0.10. Round your answers to three decimal places, and round any interim calculations to four decimal places. Fill in the hypotheses below where p₁ denotes the proportion of women who developed cervical cancer in the Gardisil group and P2 denotes the proportion of women who developed cervical…arrow_forwardIn August and September 2005 , Hurricanes Katrina and Rita caused extraordinary flooding in New Orleans, Louisiana. Many homes were severely damaged or destroyed, and of those that survived, many required extensive cleaning. It was thought that cleaning flood-damaged homes might present a health hazard due to the large amounts of mold present in many of the homes. In a sample of 350 residents of Orleans Parish who had participated in the cleaning of one or more homes, 50 had experienced symptoms of wheezing, and in a sample of 176 residents who had not participated in the cleaning, 42 reported wheezing symptoms (numbers read from a graph). Can you conclude that there is a difference between the proportion of residents with wheezing symptoms who cleaned flood-damaged homes and those who did not participate in the cleaning? Let p1 denote the proportion of residents with wheezing symptoms who had cleaned flood-damaged homes and p2 denote the proportion of…arrow_forward
- MATLAB: An Introduction with ApplicationsStatisticsISBN:9781119256830Author:Amos GilatPublisher:John Wiley & Sons IncProbability and Statistics for Engineering and th...StatisticsISBN:9781305251809Author:Jay L. DevorePublisher:Cengage LearningStatistics for The Behavioral Sciences (MindTap C...StatisticsISBN:9781305504912Author:Frederick J Gravetter, Larry B. WallnauPublisher:Cengage Learning
- Elementary Statistics: Picturing the World (7th E...StatisticsISBN:9780134683416Author:Ron Larson, Betsy FarberPublisher:PEARSONThe Basic Practice of StatisticsStatisticsISBN:9781319042578Author:David S. Moore, William I. Notz, Michael A. FlignerPublisher:W. H. FreemanIntroduction to the Practice of StatisticsStatisticsISBN:9781319013387Author:David S. Moore, George P. McCabe, Bruce A. CraigPublisher:W. H. Freeman