<prompt> In a study 400 smokers and 600 non-smokers were followed up over a period oflO years to find out the incidence of hypertension. The following table summarizes the data at the end of the study: Hypertension YesNoTotalSmokingYes120280400 No30570600 Total1508501000Calculate the risk ratio in this study is:0.060.6660  <response>: Answer: C. 6. Ref Parks Textbook of PSM 22ndPg.75 Incidence in exposed smoker is 120400 0.3 Incidence in non exposed non-smoker 30600 0.05 Risk ratio Relative Risk Incidence in exposed Incidence in non exposed 0.30.05 6 RR is direct measure of strength of association. RR1 means no association. RR 1 means positive association. 