Hypertension is the most important modifiable risk factor for coronary heart disease (the leading cause of death in North America), stroke (the third leading cause), congestive heart failure, end-stage renal disease, and peripheral vascular disease.
The results of a survey or a cross-sectional study can also be used to estimate the relative risk. Kuzma uses the data from a community health survey of retirees to study the relationship between smoking and heart disease. The data are given in the table. Does the retiree have heart disease? (Is the disease present?) YES NO Total
Case control studies are observational because no intervention is attempted and no attempt is made to alter the course of the disease. The goal is to retrospectively determine the exposure to the risk factor of interest from each of the two groups of individuals: cases and controls. These studies are designed to estimate odds. Case control studies are also known as retrospective studies and case-referent studies..