As an epidemiologist, dr. thompson is interested in determining the frequency with which a specified event occurs within a particular population at a certain instant or during a particular period. this measure is known as a rate. in epidemiologic practice, an attack rate is the most commonly used method of determining the extent or frequency with which a disease is experienced by a population of individuals. in this instance, dr. thompson is interested in knowing what percentage of the individuals who attended the july 4 celebration became ill. what is the attack rate of food poisoning among the group who attended the july 4 celebration?