The Concepts of Prevalence and Incidence as Applied to the Study of Development and Duration of Disease

The proper use of prevalence and incidence data can result in an effective way to study the history of the disease process. Methodology is given whereby the progression, duration and transition of diseases can be elucidated. Prevalence and incidence have been redefined and used in an unconventional way in view of new types of data which are being generated by mass screening projects for disease which are able to discover presymptomatic and preclinical disease states.