Fundamentals of Biostatistics
8th Edition
ISBN: 9781305268920
Author: Bernard Rosner
Publisher: Cengage Learning
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Chapter 12, Problem 4P
To determine
Conduct a statistical test to test whether specified contrast is different from 0 and explain its meaning.
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Consider a cohort study to compare the mortality rate of myocardial infarction (MI) in men with sedentary work (exposed group) to men with physically active work (unexposed). If in the exposed, there were 36,000 person (man) years of observation and 126 deaths whereas the unexposed had 24,000 man-years of observation and 44 deaths.
Compute the following
a) Mortality rate in each cohort?
b) What is the relative risk of dying, comparing these 2 groups?
c) What is the attributable risk of sedentary work?
d) What is the attributable benefit of physical activity?
e) If we assume that MI is associated with the mortality in this cohort (causality), what proportion of the disease in the higher group is potentially preventable?
Compare the two separate scatterplots. In particular, how do the associtation compare between women with pets vs. women without pets? Does one group have more variation in systolic blood pressure than the other? If so, for which group? Does systolic blood pressure seem higher for common ages between the two groups? If so, for which group?
Researchers interested in lead exposure due to car exhaust sampled the blood of 52 police officers subjected to constant inhalation of automobile exhaust fumes while working traffic enforcement in a primarily urban environment. The blood samples of these officers had an average lead concentration of 124.32 µg/l and an SD of 37.74 µg/l; a previous study of individuals from a nearby suburb, with no history of exposure, found an average blood level concentration of 35 µg/l.
Write down the hypotheses that would be appropriate for testing if the police officers appear to have been exposed to a higher concentration of lead.
Explicitly state and check all conditions necessary for inference on these data.
Test the hypothesis that the downtown police officers have a higher lead exposure than the group in the previous study. Interpret your results in context.
Based on your preceding result, without performing a calculation, would a 99% confidence interval for the average blood concentration…
Chapter 12 Solutions
Fundamentals of Biostatistics
Ch. 12 - Nutrition Researchers compared protein intake...Ch. 12 - Nutrition Researchers compared protein intake...Ch. 12 - Prob. 3PCh. 12 - Prob. 4PCh. 12 - Prob. 5PCh. 12 - Pulmonary Disease Twenty-two young asthmatic...Ch. 12 - Pulmonary Disease Twenty-two young asthmatic...Ch. 12 - Prob. 8PCh. 12 - Prob. 32PCh. 12 - Gastroenterology In Table 12.39, we present data...
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