<prompt> In a village having a population of 1000, we found patients with ceain disease. The results of new diagnostic test on that disease are as follows Test Result Disease Disease Present Absent 180 400 - 20 400 What is the prevalence of the disease?0.221820  <response>: Prevalence is defined as all current cases OldNew at a given point of time Prevalence No. of all current cases of a disease at a timeEstimated total population at that time 100 And Cases are those persons having the disease controls are healthy people, without the disease In the given question, Test Results Present : Cases Absent: Controls 180 400 _ 20 400 Total 200 800 Thus, Prevalence 200200800 100 20 Ref: Park 25th edition Pgno: 69 