HW8: Data analysis
- Due Nov 22, 2021 at 3pm
- Points 100
- Questions 15
- Available after Nov 15, 2021 at 5pm
- Time Limit None
Instructions
Keep the following scenarios available as you answer the Homework Questions.
Scenario A: A prospective cohort study evaluated the association between hypertension (E) and stroke (D). The data were examined in three separate stratified analyses. Analysis A stratified according to race; analysis B stratified according to age, and analysis C stratified according to sex. Calculate the stratum specific and crude (overall) measure of association (HINT: you can use Open Epi).
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Analysis A |
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White |
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Black |
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E+ |
E- |
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E+ |
E- |
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D+ |
194 |
24 |
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D+ |
6 |
26 |
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D- |
606 |
76 |
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D- |
194 |
874 |
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800 |
100 |
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200 |
900 |
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Analysis B |
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Young age |
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Old age |
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E+ |
E- |
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E+ |
E- |
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D+ |
12 |
45 |
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D+ |
188 |
5 |
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D- |
188 |
755 |
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D- |
612 |
195 |
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200 |
800 |
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800 |
200 |
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Analysis C |
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Men |
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Women |
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E+ |
E- |
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E+ |
E- |
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D+ |
160 |
40 |
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D+ |
40 |
10 |
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D- |
240 |
360 |
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D- |
560 |
590 |
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400 |
400 |
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600 |
600 |
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Scenario B: An investigator was interested in examining the association between dietary calcium intake and bone fractures. Although the a priori criteria were met, alcohol consumption was NOT found to be acting as a confounder affecting the association between calcium and bone fracture in the study data. Nevertheless, it was confirmed that in this study population alcohol consumption was a risk factor for bone fracture.
Scenario C: In addition to the analyses described in Scenario B, the investigators went on to divide persons who reported daily soft drink intake into “once a day” and “twice or more per day” categories. They discovered that those consuming at least two soft drinks per day were at higher risk for developing GER than those in the “once a day” group.