1. The Nurses Health Study, a cohort study of hypertension and heart attacks among women, found that of the 13,422 women with hypertension 117 had a heart attack. They also found that out of the 106,541 women without hypertension, 106,416 did not have a heart attack.
A. Organize the data in a table that will be used to determine relative risk (also called risk ratio) for a heart attack.
B. Calculate the relative risk (RR) for a heart attack among those with hypertension as compared to those without hypertension.
C. Explain your answer to (B) above in narrative form.
D. Compute the risk difference for women with hypertension. Then, express your answer per 100,000.
E. Explain your answer to (D) above in narrative form.
F. Calculate the attributable proportion among total population (APt).
G. Explain your answer to (F) above in narrative form.
2. A cohort study was conducted to study the association of coffee drinking and anxiety in a population-based sample of adults. Among 10,000 coffee drinkers, 500 developed anxiety. Among the 20,000 non-coffee drinkers, 200 cases of anxiety were observed.
A. Organize the data in a table that will be used to determine relative risk of anxiety associated with coffee use.
B. Calculate the relative risk of anxiety associated with coffee use.
C. Explain your answer to (B) above in narrative form.
3. Use the data in the Table 3.1 below to answer the following questions:
Table 3.1 Death rates from lung cancer, per 1,000 people aged 35 or older/year
|
|
Death rates
|
|
Cigarette smokers
|
0.96
|
|
Nonsmokers
|
0.07
|
A. Compute the relative risk of smokers versus nonsmokers
B. Explain your answer to (A) above in narrative form.
C. Compute the risk difference for smokers (Note: the rates are already expressed per 1000 so you do not need to multiply or divide your answer per 1000. Your answer can simply be stated per 1000).
D. Explain your answer to (C) above in narrative form.
4. Tables 4.1 and 4.2 summarize the population size and number of deaths in Arizona and Alaska in 2000. Use these tables to answer the questions that follow.
Table 4.1: Population and number of deaths by age in 2000 for Arizona
|
Age in Years
|
No. of deaths
|
Population
|
% of population
|
Death rate per 1000
|
|
< 15
|
1,028
|
538,480
|
30.4
|
|
|
15-44
|
1,629
|
728,363
|
41.1
|
|
|
45-64
|
3,839
|
341,956
|
19.3
|
|
|
65+
|
8,358
|
162,094
|
9.2
|
|
|
Total
|
14,854
|
1,770,893
|
100.0
|
|
Table 4.2: Population and number of deaths by age in 2000 for Alaska
|
Age in years
|
No. of Deaths
|
Population
|
% of population
|
Death Rate per 1000
|
|
<15
|
236
|
103,004
|
34.3
|
|
|
15-44
|
388
|
149,964
|
49.9
|
|
|
45-64
|
436
|
40,699
|
13.5
|
|
|
65+
|
368
|
6,715
|
2.3
|
|
|
Total
|
1,428
|
300,382
|
100.0
|
|
Round all answers to 2 decimal places. For questions A-D, show work in the space & write the answer in table.
- Calculate the age-specific death rates per 1000 for Arizona. (2 points)
- Calculate the total crude death rate per 1000 for Arizona.
- Calculate the age-specific death rates per 1000 for Alaska. (2 points)
- Calculate the total crude death rate per 1000 for Alaska.
- How do the crude death rates (total death rate) for Arizona and Alaska compare?
- Are the age-specific death rates similar for Arizona and Alaska?
- Is the age distribution similar for the two populations?
- What likely accounts for the very different crude rates in Arizona and Alaska?
- The death rates for the two populations were age-adjusted using the US population as the standard. The age-adjusted death rate for Arizona was 8.87 deaths per 1000, and for Alaska it was 9.34 per 1000. How do these rates compare? What do these results indicate about the influence of age?