average duration of about 10 years. Results indicated that women receiving aspirin and those receiving placebo did not differ for rates of a first major cardiovascular event, death from cardiovascular causes, or fatal or nonfatal heart attacks. However, women receiving aspirin had lower rates of stroke than those receiving placebo (data from N.Engl. J. Med., vol. 352, 2005, pp. 1293-1304). Women's Aspirin Study Data Cardiovascular Events Group Mini-Stroke Stroke No Strokes Placebo 240 259 19443 Aspirin 185 219 19530 a. Use software to test independence. Show (i) assump- tions, (ii) hypotheses, (iii) test statistic, (iv) P-value, (v) conclusion in the context of this study. b. Describe the association by finding and interpreting the relative risk for the stroke category.

PM Wed Nov 3 Stats Home Insert Draw View 8). Studies have shown that drivers who use cell phones while operating a motor passenger vehicle increase their risk of an accident. To quantify this risk, the New England Journal of Medicine (January 2, 2014) reported on the risk of a crash (or near crash) for both novice and expert drivers when using a cell phone. In a sample of 371 cases of novices using a cell phone while driving, 24 resulted in a crash (or near crash). In a sample of 1,467 cases of experts using a cell phone while driving. 67 resulted in a crash (or near crash). a). Find a 93% confidence interval for p, the true crash risk (probability) for novice drivers, also indicating the ME value. Answer: ME = b). Find a 93% confidence interval for p, the true crash risk (probability) for expert drivers, also indicating the ME value. Answer: гр, ME =

Calculate an odds ratio A group of teens ages 13-17 with anxiety were chosen as cases in a case-control study. A second group of teens ages 13-17 without anxiety were chosen as controls for the same study. The researchers were investigating if attention deficient and hyperactivity disorder (ADHD) is a potential risk factor (exposure) for anxiety (outcome). The medical histories of cases and controls were examined to determine if participants had been diagnosed with ADHD between ages 8 and 10. Among cases (teens with anxiety), 77 had been diagnosed with ADHD between ages 8 and 10 and 34 had not been diagnosed with ADHD between ages 8 and 10. Among controls (teens without anxiety), 18 had been diagnosed with ADHD between ages 8 and 10 and 124 had not been diagnosed with ADHD between ages 8 and 10. Calculate the odds ratio to measure the association between being ADHD and anxiety in teens. Express your answer to the nearest tenth or 1 place past the decimal (example: 15.4).

Teenagers who do not sleep well or long enough may have a higher risk of raised blood pressure, which could lead to cardiovascular disease later in life. The odds of raised blood pressure increase 3.5 times for those who have trouble falling asleep at night or who wake up too early and 2.5 times for those with sleeping periods of fewer than 6.5 hours. A health psychologist is interested in studying teenagers who have diastolic blood pressure scores in the top 20%. Diastolic blood pressure scores for teenagers follow a normal distribution with μ = 72 and σ = 10. Use the Distributions tool to help answer the questions that follow.     The minimum z-score necessary to be in the top 20% of the diastolic blood pressure distribution is z =0.842   .   Use this z-score to determine X, the corresponding diastolic blood pressure score. X = 80.42      This score, X, is the 80th    percentile of diastolic blood pressure scores among teenagers. The percentile rank of this score is 80%…