<prompt> Relative risk formula2018Incidence of disease among non-exposed divided By Incidence of disease among exposedIncidence of disease among non-exposed minus Incidence of disease among exposedIncidence of disease among exposed divided by Incidence of disease among non-exposedIncidence of disease among exposed minus Incidence of disease among non-exposed  <response>: Estimation of disease risk associated with exposure is obtained by an index known as Relative Risk RR or risk ratio , which is defined as the ratio between the incidence of disease among exposed persons and incidence among non-exposed. It is given by the formula: Incidence among exposed incidence among non exposed. Ref:- park; pg num :- 81 