<prompt> Diagnostic power of the test is reflected by:SensitivitySpecificityPredictive valuePopulation attributable risk  <response>: Diagnostic power of a screening test: Predictive accuracy it tells the actual no. of people having the disease or not having the disease out of those shown positive or negative by a screening test Diagnostic power of a screening test to correctly identify disease: positive predictive value PPV Diagnostic power of a screening test to correctly exclude a disease: negative predictive value NPV 