Relative risk of 5 means -

Ans. is 'c' i.e., Incidence of disease is 5 times higher in exposed group * Relative risk is a direct measure of the strength of association between suspected cause and effect. For example a relative risk of 2 means that the incidence rate is 2 times higher in the exposed group as compared with unexposed - i.e., a 100% increase in risk.* On the other hand, attributable risk indicates the extent which is attributed by risk factor (exposure) to disease. For example attributable risk of 90% means 90 percent of disease among exposed is due to exposure to risk factor.* In simple words* Relative risk indicates the increased percentage of risk of developing a disease, if person is exposed to risk factor.* Attributable risk indicates the percentage of disease which is attributed by risk factor among the exposed.* Relative risk is a better index than is attributable risk for assessing the etiological role of a factor in disease.* On the other hand, attributable risk gives a better idea than does relative risk of the impact of successful preventive or public health programme might have in reducing the problem. That means attributable risk reflect the public health importance better than relative risk.