Exercise (requires using STATA)-
A study in the New England Journal of Medicine compared cardiovascular events for treatments of low-dose aspirin or placebo among 39,876 health female health care providers for an average duration of about 10 years. Results indicated that the 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 non-fatal 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:
| cardiovascevents
group | no stroke stroke |
-----------+----------------------+
placebo |19,443 499 |
aspirin |19,530 404 |
-----------+----------------------+
a. Use data to test independence of receiving/not-receiving aspirin and rates of stroke within 10 years. Show (i) assumptions, (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.