In a given population, prevalence of a disease can be rapidly determined by-

. cross sectional study is a simplest form of an observational study,which are more useful in the cases of chronic diseases.cross sectional studies are also employed in the calculation of prevalence,.it provides only very little information about the natural history of disease or about the rate of occurrence of new cases. ref:park&;s textbook of preventive and social medicine,22nd edition,pg no 67