A recent study set out to investigate the association between smoking and the development of coronary artery disease (CAD), the leading cause of heart attacks among adults in the US. Upon enrollment in the study, 1,232 adult participants were asked to report whether they had ever smoked more than one pack of cigarettes in the lifetimes. The participants were then examined for the development of CAD once a year for the following twenty years. Examinations found 106 cases of CAD among the 368 participants who had never smoked and 419 cases of CAD among the 864 participants who had ever smoked.

6)What type of study design was used? Explain.

7)Set up the 2X2 contingency table for the data.

8)For this type of study design, what is the appropriate measure to describe the strength of the association between exposure and disease?

9) Calculate the measure identified in question 8.

10) Interpret the measure calculated in question 9.