<prompt> Screening for condition recommended when-Low case fatality rateDiagnostic tools not availableNo effective treatment availableEarly diagnosis can change disease course because of effective treatment  <response>: Ref:Parks 23rd edition pg 136. Screening is carried out in the hope that earlier diagnosis and subsequent treatment, orably alters the natural history of the disease in a significant propoion of those who are identified as positive. Note: We don;t do screening when the disease has a low case fatality ratio. Diagnostic toolstests must be made available before doing a screening test. Otherwise it will be in vain. Effective treatment should be available prior to doing a screening test. Also Refer p. 135. Table 1. 