Terrence Howard plays a music mogul in a new series on Fox. CHICAGO â In the presidential suite of a Hilton hotel, above a ballroom full of extras waiting to shoot a lavish party scene, sat the two lead actors of âEmpire,â a new Fox series about a feuding entertainment-industry family.
Prevalence is a statistical concept referring to the number of cases of a disease that are present in a particular population at a given time, whereas incidence refers to the number of new cases that develop in a given period of time.
Prevalence and incidence are the fundamental measures of disease frequency, but special names have evolved for these measures, depending on their specific use. All of these tend to be referred to as rates, even though, strictly speaking, they often refer to proportions (cumulative incidence or prevalence).